Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "78.67.Hc" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-50 z 109
Tytuł:
Energy Spectrum of InAs Quantum Dots in GaAs/AlAs Superlattices
Autorzy:
Nedzinskas, R.
Čechavičius, B.
Kavaliauskas, J.
Karpus, V.
Krivaitė, G.
Tamošiūnas, V.
Valušis, G.
Schrey, F.
Unterrainer, K.
Strasser, G.
Powiązania:
https://bibliotekanauki.pl/articles/1813385.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
Opis:
Photo- and contactless electroreflectance spectroscopies were applied to study optical properties and electronic structure of GaAs/AlAs superlattice systems with embedded InAs quantum dots. The observed interband transitions related to the quantum dot ground and excited states, as well as optical transitions in the combined system formed by the InAs wetting layer and GaAs/AlAs superlattice are discussed.
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 975-978
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Two-Photon Coherent Polarization Flipping of Confined Excitons
Autorzy:
Machnikowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/2047682.pdf
Data publikacji:
2007-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
Opis:
A two-photon process leading to coherent transitions between the two circularly polarized exciton states in a quantum dot is studied. It is shown that optical flipping of the exciton polarization is possible with picosecond laser pulses. The process is closely related to two-photon Rabi oscillations of a biexciton but it is much more stable against shifts of the laser frequency.
Źródło:
Acta Physica Polonica A; 2007, 112, 2; 289-293
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical Properties of InAs Quantum Dots
Autorzy:
Willander, M.
Zhao, Q. X.
Jacob, A. P.
Wang, S. M.
Wei, Y. Q.
Powiązania:
https://bibliotekanauki.pl/articles/2035579.pdf
Data publikacji:
2002
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Cr
Opis:
InAs quantum dots grown on GaAs substrate were investigated by optical spectroscopy. We particularly emphasized on the photoluminescence intensity, the stability of the photoluminescence intensity versus temperatures and wavelength of the InAs dot emission at various thermal treatments and different structures. We found that hydrogen can strongly passivate nonradiative centers without causing any structure degradation, and both n- and p-type modulation doping can reduce the decrease in the photoluminescence intensity when the sample temperature increases from the helium temperature to room temperature. The emission wavelength and the efficiency of the InAs quantum dots can also be manipulated by choosing proper materials of cap layer.
Źródło:
Acta Physica Polonica A; 2002, 102, 4-5; 567-576
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Signatures of p-Shell Electron g-Factor in s-Shell Emission of CdTe/ZnTe Quantum Dots
Autorzy:
Kazimierczuk, T.
Goryca, M.
Wojnar, P.
Golnik, A.
Nawrocki, M.
Kossacki, P.
Powiązania:
https://bibliotekanauki.pl/articles/1492860.pdf
Data publikacji:
2011-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Et
78.67.Hc
Opis:
We analyze the photoluminescence of excitonic complexes containing p-shell electron in the magnetic field in the Faraday configuration. We demonstrate that despite the p-shell electron is not involved directly in the recombination process, its g-factor influences the emission spectrum. We found that in the case of CdTe/ZnTe quantum dots the p-shell electron is significantly less affected by the magnetic field than s-shell electron in the same dot.
Źródło:
Acta Physica Polonica A; 2011, 120, 5; 874-876
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Four-Wave Mixing Spectroscopy of Quantum Dot Molecules
Autorzy:
Sitek, A.
Machnikowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/2047371.pdf
Data publikacji:
2007-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.47.+p
Opis:
We study theoretically the nonlinear four-wave mixing response of an ensemble of coupled pairs of quantum dots (quantum dot molecules). We discuss the shape of the echo signal depending on the parameters of the ensemble: the statistics of transition energies and the degree of size correlations between the dots forming the molecules.
Źródło:
Acta Physica Polonica A; 2007, 112, 2; 167-172
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Single GaN/AlGaN Quantum Dot Spectroscopy
Autorzy:
Surowiecka, K.
Wysmołek, A.
Stępniewski, R.
Bożek, R.
Pakuła, K.
Baranowski, J. M.
Powiązania:
https://bibliotekanauki.pl/articles/2047382.pdf
Data publikacji:
2007-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
Microphotoluminescence of low-density GaN/Al$\text{}_{x}$Ga$\text{}_{1-x}$N quantum dots grown by metal-organic vapor phase epitaxy using in situ etching of AlGaN is presented. The detailed analysis of the emission from these structures enables the observation of pairs of lines separated by the energy up to 3 meV. They behave in a different way under different excitation power that suggests that this doublet structure can be associated with the exciton and trion (or biexciton recombination). It is observed that for different quantum dots the energy of the charged exciton complex emission could be higher or lower than the neutral exciton one. It is discussed in terms of a competition between attractive e-h and repulsive e-e (h-h) Coulomb interaction that occurs because of the existence of the built-in electric field that separates electrons and holes in the dot.
Źródło:
Acta Physica Polonica A; 2007, 112, 2; 233-236
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Inter-Dot Coupling in a Self-Assembled Quantum Dot System
Autorzy:
Kazimierczuk, T.
Nowak, S.
Suffczyński, J.
Wojnar, P.
Golnik, A.
Gaj, J. A.
Kossacki, P.
Powiązania:
https://bibliotekanauki.pl/articles/2047689.pdf
Data publikacji:
2007-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Et
Opis:
We present studies of resonant excitation of self-assembled CdTe/ZnTe quantum dots. Photoluminescence excitation measurements revealed existence of sharp resonances, common for photoluminescence lines attributed to different quantum dot charge states. We conclude from the ensemble of photoluminescence and photoluminescence excitation results that we observe energy transfer in coupled quantum dot pairs.
Źródło:
Acta Physica Polonica A; 2007, 112, 2; 321-324
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Configuration Mixing on Energies and Recombination Dynamics of Excitonic States in CdTe/ZnTe Quantum Dots
Autorzy:
Smoleński, T.
Kazimierczuk, T.
Goryca, M.
Kossacki, P.
Gaj, J. A.
Wojnar, P.
Fronc, K.
Korkusiński, M.
Hawrylak, P.
Powiązania:
https://bibliotekanauki.pl/articles/2047951.pdf
Data publikacji:
2011-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Et
Opis:
We study experimentally and theoretically excitonic recombination processes in CdTe/ZnTe quantum dots. The single quantum dot photoluminescence spectrum was observed and emission lines from X, X$\text{}^{-}$, X$\text{}^{+}$ and 2X excitonic states were identified. Experimental results were analysed in the theoretical model based on the effective mass approximation. Numerical calculations of energy positions and recombination probabilities of X, X$\text{}^{-}$, X$\text{}^{+}$ and 2X were performed. Computed results reproduce correctly the order and relative positions of emission lines and ratios of radiative lifetimes.
Źródło:
Acta Physica Polonica A; 2011, 119, 5; 615-617
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Temporal Evolution of Multi-Carrier Complexes in Single GaN/AlGaN Quantum Dots
Autorzy:
Surowiecka, K.
Wysmołek, A.
Stępniewski, R.
Bożek, R.
Pakuła, K.
Baranowski, J. M.
Powiązania:
https://bibliotekanauki.pl/articles/2044542.pdf
Data publikacji:
2005-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
Microphotoluminescence of low-density GaN/Al$\text{}_{x}$Ga$\text{}_{1-x}$N quantum dots grown by metal-organic vapor phase epitaxy using in situ etching of AlGaN is presented. The narrow lines in the microphotoluminescence spectra due to the single quantum dots are observed. Both energy and intensity of these lines show temporal fluctuations. Statistical analysis based on the correlation matrix allowed us to identify objects, which are affected by photo-induced electric field fluctuations. Relations between emission lines participating in the spectrum are discussed.
Źródło:
Acta Physica Polonica A; 2005, 108, 5; 879-884
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electron Spins in Self-Assembled (In,Ga)As/GaAs Quantum Dots Studied by Pump-Probe Faraday Rotation
Autorzy:
Greilich, A.
Yugova, I. A.
Oulton, R.
Zhukov, E. A.
Yakovlev, D. R.
Bayer, M.
Shabaev, A.
Efros, Al. L.
Stavarache, V.
Reuter, D.
Wieck, A. D.
Powiązania:
https://bibliotekanauki.pl/articles/2046975.pdf
Data publikacji:
2006-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
Static and dynamic properties of electron spins in self-assembled (In,Ga)As/GaAs quantum dots which contain on average a single electron per dot were studied by pump-probe Faraday rotation. Examples given here are the g-factor tensor components as well as the dephasing time T*$\text{}_{2}$ within a dot ensemble.
Źródło:
Acta Physica Polonica A; 2006, 110, 3; 287-293
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Emission of Self-Assembled CdTe/ZnTe Quantum Dot Samples with Different Cap Thickness
Autorzy:
Nowak, S.
Powiązania:
https://bibliotekanauki.pl/articles/1791338.pdf
Data publikacji:
2009-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Et
78.67.Hc
Opis:
Photoluminescence measurements on CdTe/ZeTe self-assembled quantum dot samples with different cap thickness values (18-110nm) were performed at 1.8 K at varying excitation levels. The shape of macrophotoluminescence spectra did not altered notably with the excitation power. The spectra exhibited interference fringes related to the total barrier thickness. Simulation of the fringes confirmed the barrier thickness determined during the growth. The minimal amplitude of the fringes was observed for the cap thickness corresponding approximately to a quarter of the emission wavelength in the barrier material. Maximum emission intensity occurred for the largest thickness of the cap, i.e., 110 nm. We attribute this result to the influence of the surface recombination centers.
Źródło:
Acta Physica Polonica A; 2009, 116, 5; 890-892
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Time Evolution of the Microluminescence Energy οf GaN/AlGaN Quantum Dots
Autorzy:
Surowiecka, K.
Wysmołek, A.
Stępniewski, R.
Bożek, R.
Pakuła, K.
Baranowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1791354.pdf
Data publikacji:
2009-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
Time evolution of the microphotoluminescence from low-density GaN/$Al_{x}Ga_{1-x}N$ quantum dots grown by metal organic chemical vapor deposition using in situ etching of AlGaN is presented. The observed effect is related to the energy changes that begin immediately after sample illumination with the exciting laser light and saturate after some time. Typically, the luminescence energy decreases and the change is exponential with characteristic times in a range between several dozen and several hundred seconds. However, sometimes we observed the energy increase with characteristic times in a range between several and a few hundred seconds. The obtained results are discussed in terms of the metastable change of the electric field, induced by spontaneous polarization present in GaN/AlGaN structure (in the growth direction), and strain- or defect-induced changes of the electric field in the vicinity of the dot.
Źródło:
Acta Physica Polonica A; 2009, 116, 5; 933-935
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fine Structure of Neutral Excitons in Single GaAlAs Quantum Dots
Autorzy:
Molas, M.
Gołasa, K.
Piętka, B.
Potemski, M.
Babiński, A.
Powiązania:
https://bibliotekanauki.pl/articles/1403612.pdf
Data publikacji:
2012-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
Optical anisotropy of neutral excitons in GaAlAs/AlAs quantum dots is investigated. Low-temperature polarization-sensitive photoluminescence measurements of single quantum dots are performed. It is found that neutral excitons (X) in the quantum dots exhibit a fine structure splitting. The fine structure splitting ranges from 10 μeV to 100 μeV and correlates with the X energy. The polarization axis of the fine structure splitting is well oriented along [110] crystallographic direction of a substrate. The orientation is attributed to the elongation of GaAlAs/AlAs quantum dots in the [110] direction of the substrate.
Źródło:
Acta Physica Polonica A; 2012, 122, 6; 988-990
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Fine Structure of a Triexciton in Single InAs/GaAs Quantum Dots
Autorzy:
Molas, M.
Gołasa, K.
Furman, M.
Lapointe, J.
Wasilewski, Z.
Potemski, M.
Babiński, A.
Powiązania:
https://bibliotekanauki.pl/articles/1403615.pdf
Data publikacji:
2012-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
Results of experimental study of multiexcitonic emission related to the p-shell of single self-assembled InAs/GaAs quantum dots are presented. Optical properties of a first emission line to appear from the p-shell of a strongly excited quantum dots are investigated using low-temperature polarization-sensitive micro-photoluminescence measurements. The emission line is attributed to the recombination of a complex of three electrons and holes confined in a dot (neutral triexciton), 3X. It is found that the emission consists of two linearly polarized components and the fine structure splitting is larger than the respective splitting of a neutral exciton. The optical anisotropy of the 3X emission is related to the anisotropy of the quantum dot localizing potential. The axis of the 3X optical anisotropy changes from dot to dot covering broad range within ± 50 degrees with respect to the axis defined by the optical anisotropy of a neutral exciton (X). Possible origin of the deviation is discussed.
Źródło:
Acta Physica Polonica A; 2012, 122, 6; 991-993
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Properties of Excitons in Quantum Dots with a Weak Confinement
Autorzy:
Gołasa, K.
Molas, M.
Goryca, M.
Kazimierczuk, T.
Smoleński, T.
Koperski, M.
Golnik, A.
Kossacki, P.
Potemski, M.
Wasilewski, Z.
Babiński, A.
Powiązania:
https://bibliotekanauki.pl/articles/1399080.pdf
Data publikacji:
2013-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
Statistical properties of neutral excitons, biexcitons and trions confined to natural quantum dots formed in the InAs/GaAs wetting layer are reported. The correlation of the trion binding energy and the biexciton binding energy was found. Magnetospectroscopic measurements of the excitons revealed also the correlation of excitonic effective $g^\ast $ factor of an exciton with the biexciton binding energy. The qualitative picture of the effect of quantum confinement on the observed correlations is presented.
Źródło:
Acta Physica Polonica A; 2013, 124, 5; 781-784
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Statistical Study of the Inter-Dot Excitation Transfer in CdTe/ZnTe Quantum Dots
Autorzy:
Koperski, M.
Kazimierczuk, T.
Goryca, M.
Golnik, A.
Gaj, J.
Nawrocki, M.
Wojnar, P.
Kossacki, P.
Powiązania:
https://bibliotekanauki.pl/articles/1492874.pdf
Data publikacji:
2011-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Et
Opis:
In this work we present a statistical study of resonantly excited luminescence of coupled CdTe/ZnTe quantum dots studied by photoluminescence excitation measurements. We investigate the probability of resonance occurrence as a function of resonant energy. We come to the conclusion that the distribution of the inter-dot resonances is uniform, which suggests that the inter-dot excitation transfer is not limited by mean density of states in the emitting quantum dots.
Źródło:
Acta Physica Polonica A; 2011, 120, 5; 880-882
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Anisotropic Exchange Interaction between p-Shell Electron and s-Shell Hole in CdTe/ZnTe Quantum Dots
Autorzy:
Kazimierczuk, T.
Golnik, A.
Goryca, M.
Wojnar, P.
Gaj, J.
Kossacki, P.
Powiązania:
https://bibliotekanauki.pl/articles/1791334.pdf
Data publikacji:
2009-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Et
Opis:
We study electron-hole exchange interaction in a single CdTe/ZnTe quantum dot by polarization-resolved photoluminescence measurements. We focus on recombination of excitonic states involving p-shell electrons: $X^{2-}$ and $XX^-$. Recombination lines of $X^{2-}$ and $XX^-$ states exhibit fine structure, which can be consistently explained within a model with four parameters $δ_{i}^{αβ}$ representing strength of iso- and anisotropic parts of interaction between s-hole and s- or p-electron.
Źródło:
Acta Physica Polonica A; 2009, 116, 5; 882-884
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Control of Local Electric Fields Influencing the Photoluminescence οf an Individual CdTe/ZnTe Quantum Dot
Autorzy:
Haas, K.
Kazimierczuk, T.
Wojnar, P.
Golnik, A.
Gaj, J.
Kossacki, P.
Powiązania:
https://bibliotekanauki.pl/articles/1791340.pdf
Data publikacji:
2009-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Et
Opis:
We examine the influence of a weak non-resonant illumination on the quantum dot photoluminescence spectrum. We observe that even very weak illumination affects both intensity and spectral position of emission lines in the spectrum. We discover no significant asymmetry in spatial dependence and infer that the observed effects cannot be attributed to a single neighbor center.
Źródło:
Acta Physica Polonica A; 2009, 116, 5; 896-898
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effective Green Semiconductor Lasers with Multiple CdSe/ZnSe QD Active Region for Electron Beam Pumping
Autorzy:
Gronin, S.
Sorokin, S.
Sedova, I.
Kop'ev, P.
Ivanov, S.
Zverev, M.
Gamov, N.
Peregoudov, D.
Studionov, V.
Powiązania:
https://bibliotekanauki.pl/articles/1811929.pdf
Data publikacji:
2008-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Et
78.67.Hc
Opis:
The characteristics of ZnSe-based electron beam pumped semiconductor lasers are presented in detail. The laser structures consist of a 0.6 μm thick superlattice waveguide centered with ten equidistantly placed CdSe/ZnSe quantum dot active layers. The maximum light output pulse power of 12 W per facet at room temperature along with an extremely high quantum efficiency of ≈8.5% were obtained at an electron beam pumping energy of 23 keV (the laser wavelength is of 542 nm). The calculations of a spatial distribution of non-equilibrium carrier concentration within the semiconductor structures under electron beam pumping are presented. The possible ways of further improvement of laser efficiency are discussed.
Źródło:
Acta Physica Polonica A; 2008, 114, 5; 1115-1122
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spin in CdTe/ZnTe Quantum Dot: Its Potential for Information Storage
Autorzy:
Kazimierczuk, T.
Powiązania:
https://bibliotekanauki.pl/articles/1807600.pdf
Data publikacji:
2009-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Et
Opis:
We present a selection of our studies on CdTe/ZnTe quantum dots considered as spin qubits. Discussed experiments are related to processes of spin reading, writing and evolution. We show that CdTe/ZnTe system is well suitable for studying effects important for optical quantum computing on single spins.
Źródło:
Acta Physica Polonica A; 2009, 116, S; S-13-S-18
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Real-Space Mapping of Exciton Wave Functions in a Quantum Dot with Near-Field Optical Imaging Spectroscopy
Autorzy:
Saiki, T.
Matsuda, K.
Nomura, S.
Mihara, M.
Aoyagi, Y.
Nair, S.
Takagahara, T.
Powiązania:
https://bibliotekanauki.pl/articles/2036895.pdf
Data publikacji:
2003
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
An exciton confined within a quantum dot acts as a two-level quantum system, and is one of the most promising candidates for quantum computing and quantum information processing. The real-space optical probing of the quantum eigenstates in a single quantum dot and coupled quantum dots should be developed toward the realization of quantum photonic devices, where their wave functions are dynamically controlled by coherent optical techniques. Here we apply near-field photoluminescence imaging spectroscopy with a high spatial resolution of 30 nm to map out the centre-of-mass wave function of an exciton confined in a GaAs quantum dot. The spatial profile of the exciton emission, which reflects the shape of a monolayer-high island, differs from that of biexciton emission, due to different distributions of the polarization field for the exciton and biexciton recombinations.
Źródło:
Acta Physica Polonica A; 2003, 104, 3-4; 281-287
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Excitation Mechanisms of CdTe/ZnTe Quantum Dots under Non-Resonant and Quasi-Resonant Regime
Autorzy:
Kazimierczuk, T.
Gaj, J. A.
Golnik, A.
Goryca, M.
Nawrocki, M.
Koperski, M.
Smoleński, T.
Suffczyński, J.
Wojnar, P.
Kossacki, P.
Powiązania:
https://bibliotekanauki.pl/articles/2047917.pdf
Data publikacji:
2011-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Et
Opis:
We discuss possible mechanisms of quantum dot population control. A set of experiments, including time-resolved photoluminescence, single photon correlations, excitation correlation, and photoluminescence excitation is used to determine the actual mechanism under non-resonant and quasi-resonant regime.
Źródło:
Acta Physica Polonica A; 2011, 119, 5; 588-591
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantum Confinement in InAs/GaAs Systems with Self-Assembled Quantum Dots Grown Using In-Flush Technique
Autorzy:
Molas, M.
Kuldová, K.
Borysiuk, J.
Wasilewski, Z.
Babiński, A.
Powiązania:
https://bibliotekanauki.pl/articles/2048050.pdf
Data publikacji:
2011-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Cr
78.67.Hc
Opis:
The effect of In-flush technique application to the MBE-grown structure with self-assembled quantum dots is investigated in this work. The microphotoluminescence from structures with the InAs/GaAs dots grown with and without the In-flush has been investigated. We focus our attention on "not fully developed" dots, which can be clearly distinguished in the spectrum. The dots have also been identified in the transmission electron microscopy analysis of the structures. The In-flush does not influence a broad energy range of those features. Instead we have found that the anisotropic exchange energy splitting of neutral excitons confined in those in the structure grown with In-flush is substantially lower that the splitting in the structure with no In-flush. This observation confirms that the In-flush leads not only to better uniformity of self-assembled quantum dots but also to reduction of lateral potential, anisotropy, which is believed to result in the neutral exciton splitting.
Źródło:
Acta Physica Polonica A; 2011, 119, 5; 624-626
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of an Electric Field on Fine Properties of III-V and II-VI Quantum Dots Systems
Autorzy:
Kowalik, K.
Krebs, O.
Kudelski, A.
Golnik, A.
Lemaître, A.
Senellart, P.
Karczewski, G.
Kossut, J.
Gaj, J.
Voisin, P.
Powiązania:
https://bibliotekanauki.pl/articles/2038219.pdf
Data publikacji:
2004-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
71.70.Ej
Opis:
We investigate the influence of an electric field on the optical properties of single quantum dots. For sample made of III-V compounds micron-size electro-optical structures were produced in order to apply an electric field in the dot plane. For several individual dots lines significant variations of the anisotropic exchange splitting with the field were observed. On sample made of II-VI compounds we demonstrate the influence of electric field fluctuations on the luminescence of a single quantum dot.
Źródło:
Acta Physica Polonica A; 2004, 106, 2; 177-184
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spin-Dependent Coupling of Charged Quantum Dot Excitons with Continuum States
Autorzy:
Urbaszek, B.
Warburton, R. J.
Karrai, K.
Schulhauser, C.
Högele, A.
McGhee, E. J.
Govorov, A. O.
Gerardot, B. D.
Marie, X.
Amand, T.
Petroff, P. M.
Powiązania:
https://bibliotekanauki.pl/articles/2038350.pdf
Data publikacji:
2004-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.21.La
78.67.Hc
Opis:
Magnetic field and temperature dependent photoluminescence studies on neutral and charged excitons in individual InAs quantum dots allow us to uncover different mechanisms by which the discrete quantum dot states are coupled to delocalized continuum states in a quantum well (the wetting layer). The behaviour of the neutral and singly charged excitons can be explained taking only discrete quantum dot states into account. For doubly and triply charged excitons we have to consider spin dependent coherent and incoherent interactions between discrete quantum dot states and delocalized wetting layer states.
Źródło:
Acta Physica Polonica A; 2004, 106, 3; 395-402
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Temperature Dependence of Photoluminescence from Epitaxial InGaAs/GaAs Quantum Dots with High Lateral Aspect Ratio
Autorzy:
Musiał, A.
Sęk, G.
Maryński, A.
Podemski, P.
Misiewicz, J.
Löffler, A.
Höfling, S.
Reitzenstein, S.
Reithmaier, J.
Forchel, A.
Powiązania:
https://bibliotekanauki.pl/articles/1492876.pdf
Data publikacji:
2011-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
65.80.-g
Opis:
Hereby, we present a study of a thermal quenching of emission from self-assembled epitaxial highly asymmetric quantum dots in InGaAs/GaAs material system for both ensemble and single dot regime. Pronounced interplay between the intensity of wetting layer and quantum dots originated emission was observed as the temperature was increased, evidencing a thermally activated energy transfer between the two parts of the system and an important role of the wetting layer in determining the optical properties of these anisotropic nanostructures. The carrier activation energies have been derived and possible carrier loss mechanisms have been analyzed. Single dot study revealed activation energies slightly varying from dot to dot due to size and shape distribution. The problem of the shape uniformity of individual quantum dot has also been addressed and possibility of additional carrier localization within the investigated structures has been found to be insignificant based on the recorded spectroscopic data.
Źródło:
Acta Physica Polonica A; 2011, 120, 5; 883-887
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical Properties of CdTe QDs Formed Using Zn Induced Reorganization
Autorzy:
Kobak, J.
Pacuski, W.
Jakubczyk, T.
Kazimierczuk, T.
Golnik, A.
Frank, K.
Rosenauer, A.
Kruse, C.
Hommel, D.
Gaj, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/2048054.pdf
Data publikacji:
2011-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
81.07.Ta
78.67.Hc
Opis:
In this paper we present optical studies of CdTe quantum dots formed using Zn-induced reorganization. The pattern of quantum dot photoluminescence lines is found to be similar to typical results reported for quantum dots grown with other techniques, although the positively charged exciton line is relatively more pronounced. Also the energy spacing between biexciton and exciton lines is found to be larger than in typical results. Zn-induced reorganization results in quantum dots density higher by an order of magnitude than in Te-induced quantum dots.
Źródło:
Acta Physica Polonica A; 2011, 119, 5; 627-629
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Optical Excitonic Aharonov-Bohm Effect in a Few Nanometer Wide Type-I Nanorings
Autorzy:
Tadić, M.
Arsoski, V.
Čukarić, N.
Peeters, F.
Powiązania:
https://bibliotekanauki.pl/articles/1537808.pdf
Data publikacji:
2010-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.21.La
78.67.Hc
Opis:
The optical excitonic Aharonov-Bohm effect in type-I three-dimensional (In,Ga)As/GaAs nanorings is theoretically explored. The single-particle states of the electron and the hole are extracted from the effective mass theory in the presence of inhomogeneous strain, and an exact numerical diagonalization approach is used to compute the exciton states and the oscillator strength $f_{x}$ for exciton recombination. We studied both the large lithographically-defined and small self-assembled rings. Only in smaller self-assembled nanorings we found optical excitonic Aharonov-Bohm effect. Those oscillations are established by anticrossings between the optically active exciton states with zero orbital momentum. In lithographically defined rings, whose average radius is 33 nm, $f_{x}$ shows no oscillations, whereas in the smaller self-assembled nanoring with average radius of 11.5 nm oscillations in $f_{x}$ for the ground exciton state are found as function of the magnetic field that is superposed on a linear dependence. These oscillations are smeared out at finite temperature, thus photoluminescence intensity exhibits step-like variation with magnetic field even at temperature as small as 4.2 K.
Źródło:
Acta Physica Polonica A; 2010, 117, 6; 974-977
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interband Optical Properties of Concentric Type-I Nanorings in a Normal Magnetic Field
Autorzy:
Arsoski, V.
Tadić, M.
Peeters, F.
Powiązania:
https://bibliotekanauki.pl/articles/1537829.pdf
Data publikacji:
2010-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.21.La
78.67.Hc
Opis:
Two concentric two-dimensional GaAs/(Al,Ga)As nanorings in a normal magnetic field are theoretically studied. The single-band effective mass approximation is adopted for both the electron and the hole states, and the analytical solutions are given. We find that the electronic single particle states are arranged in pairs, which exhibit anticrossings and the orbital momentum transitions in the energy spectrum when magnetic field increases. Their period is essentially determined by the radius of the outer ring. The oscillator strength for interband transitions is strongly reduced close to each anticrossing. We show that an optical excitonic Aharonov-Bohm effect may occur in concentric nanorings.
Źródło:
Acta Physica Polonica A; 2010, 117, 5; 733-737
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carrier Trapping in a Quantum Dash: Optical Signatures
Autorzy:
Kaczmarkiewicz, P.
Machnikowski, P.
Kuhn, T.
Powiązania:
https://bibliotekanauki.pl/articles/1403618.pdf
Data publikacji:
2012-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
73.21.La
Opis:
We theoretically study the optical properties and the electronic structure of highly elongated quantum dots (quantum dashes) and show how geometrical fluctuations affect the excitonic spectrum of the system. The dependence of the absorption intensities on the geometrical properties (depth and length) of the trapping center in a quantum dash is analyzed and the dependence of the degree of the linear polarization on these geometrical parameters is studied.
Źródło:
Acta Physica Polonica A; 2012, 122, 6; 997-1000
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Phonon-Assisted Radiative Recombination of Excitons Confined in InAs Quantum Dashes
Autorzy:
Dusanowski, Ł.
Musiał, A.
Sęk, G.
Machnikowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/1399092.pdf
Data publikacji:
2013-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
63.20.kk
Opis:
In this report we have investigated theoretically the phonon-assisted recombination process of excitons confined in strongly elongated semiconductor nanostructures, called quantum dashes. Interaction with phonon bath leads to the occurrence of phonon-assisted recombination, which in the case of acoustic phonons is manifested in the optical spectra as a deviation of the homogeneously broadened emission line shape from expected Lorentzian profile via occurrence of the so-called phonon sidebands. Hereby, we have modeled the influence of the quantum dash geometry on this spectral feature proving pronounced suppression of phonon-induced decoherence for strongly elongated nanostructures. Furthermore, the importance of different phonon coupling mechanisms has been evaluated and the spectral diffusion effects, unavoidable in the time-integrated photoluminescence experiments, have been accounted for.
Źródło:
Acta Physica Polonica A; 2013, 124, 5; 813-816
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photon Correlations and Cross-Correlations from a Single CdTe/ZnTe Quantum Dot
Autorzy:
Couteau, C.
Moehl, S.
Suffczyński, J.
Gaj, J. A.
Tinjod, F.
Gérard, J. M.
Kheng, K.
Mariette, H.
Romestain, R.
Poizat, J. P.
Powiązania:
https://bibliotekanauki.pl/articles/2038216.pdf
Data publikacji:
2004-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
42.50.Dv
Opis:
We report correlation and cross-correlation continuous wave measurements in II-VI quantum dots grown by molecular beam epitaxy. Combination of spectral selection, saturation measurements and good temporal resolution allowed us to see an antibunching effect on photons from radiative recombination of excitons in a single CdTe/ZnTe quantum dot, as well as cross-correlation within the biexciton (X$\text{}_{2}$)-exciton (X) radiative cascade from the same dot. We discuss the results of our experiments in terms of a model of excitonic multitransitions.
Źródło:
Acta Physica Polonica A; 2004, 106, 2; 169-176
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Self-Assembled CdTe/ZnTe Quantum Dots
Autorzy:
Kowalik, K.
Kudelski, A.
Golnik, A.
Gaj, J. A.
Karczewski, G.
Kossut, J.
Powiązania:
https://bibliotekanauki.pl/articles/2035754.pdf
Data publikacji:
2003-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
71.70.Ej
Opis:
We present microluminescence investigations of self-assembled CdTe/ZnTe quantum dots. The dots proprieties resulting from our studies are: values of optical in-plane anisotropy parameters (electron - heavy hole exchange splitting and orientation of anisotropy) and value of effective Lande factor. Parameters giving information about in-plane anisotropy possess random distribution of values with the exchange splitting from 0 to 240 μeV. The effective Lande factor values for our dots are around g$\text{}^{*}$=-3.2 with a scatter of about 18%. Some PL lines exhibit sudden jumps of energetic position, related to variation of the charge state in their neighborhood.
Źródło:
Acta Physica Polonica A; 2003, 103, 6; 539-544
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hole Subband Mixing and Polarization of Luminescence from Quantum Dashes: A Simple Model
Autorzy:
Kaczmarkiewicz, P.
Musiał, A.
Sęk, G.
Podemski, P.
Machnikowski, P.
Misiewicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/2048063.pdf
Data publikacji:
2011-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
73.22.-f
Opis:
In this paper, we address the problem of luminescence polarization in the case of nanostructures characterized by an in-plane shape asymmetry. We develop a simple semi-qualitative model revealing the mechanism that accounts for the selective polarization properties of such structures. It shows that they are not a straightforward consequence of the geometry but are related to it via valence subband mixing. Our model allows us to predict the degree of polarization dependence on the in-plane dimensions of investigated structures assuming a predominantly heavy hole character of the valence band states, simplifying the shape of confining potential and neglecting the influence of the out-of-plane dimension. The energy dependence modeling reveals the importance of different excited states in subsequent spectral ranges leading to non-monotonic character of the degree of polarization. The modeling results show good agreement with the experimental data for an ensemble of InAs/InP quantum dashes for a set of realistic parameters with the heavy-light hole states separation being the only adjustable one. All characteristic features are reproduced in the framework of the proposed model and their origin can be well explained and understood. We also make some further predictions about the influence of both the internal characteristics of the nanostructures (e.g. height) and the external conditions (excitation power, temperature) on the overall degree of polarization.
Źródło:
Acta Physica Polonica A; 2011, 119, 5; 633-636
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of Optical Transitions from CdTe and CdMnTe Quantum Dots Embedded in ZnTe Nanowires
Autorzy:
Szymura, M.
Kłopotowski, Ł.
Wojnar, P.
Karczewski, G.
Wojtowicz, T.
Kossut, J.
Powiązania:
https://bibliotekanauki.pl/articles/1399096.pdf
Data publikacji:
2013-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Et
78.67.Uh
78.67.Hc
Opis:
We study photoluminescence properties of CdTe and CdMnTe quantum dots embedded in ZnTe nanowires. The nanowires were grown by molecular beam epitaxy, applying the vapor-liquid-solid growth mechanism. Linear polarization anisotropy measurements allow us to assess that the excitonic transitions originate from a single nanowire. We identify the optical transitions by comparing observed spectroscopic shifts with the universal emission pattern from the epitaxial CdTe dots. We support this identification by analyzing the photoluminescence intensity dependence on excitation power.
Źródło:
Acta Physica Polonica A; 2013, 124, 5; 824-826
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Sub-Nanosecond Phase Recovery in Quantum-Dot Semiconductor Optical Amplifiers
Autorzy:
Abedi, K.
Taleb, H.
Powiązania:
https://bibliotekanauki.pl/articles/1399957.pdf
Data publikacji:
2013-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.55.Eq
78.67.-n
78.67.Hc
Opis:
In this paper, optimal design of a pumping scheme for achieving the best gain and phase response in quntum-dot semiconductor optical amplifiers is investigated. For the first time, the dynamic response of the quntum-dot semiconductor optical amplifier is evaluated under three different pumping schemes, known as optical pumping, electrical pumping, and electro-optical pumping. Simulation results show that the shortest gain recovery time in quntum-dot semiconductor optical amplifiers can be achieved under the electrical pumping scheme. However, under the optical pumping and electro-optical pumping schemes, the quntum-dot semiconductor optical amplifier represents a shorter phase recovery compared to the electrical pumping scheme. We found that a sub-nanosecond phase recovery in the quntum-dot semiconductor optical amplifier can be achieved under the OP and electro-optical pumping schemes, which can never be achieved under the electrical pumping, because of the slow carrier dynamics of the carrier reservoir. Also, it was found that the gain recovery process in an optically pumped quntum-dot semiconductor optical amplifier can be significantly accelerated at cryogenic temperatures. This result demonstrates the superiorities of the optical pumping scheme over the electrical pumping and electro-optical pumping schemes at low temperatures, where both the gain and phase recovery times of an optically pumped quantum-dot semiconductor optical amplifier are drastically decreased.
Źródło:
Acta Physica Polonica A; 2013, 123, 2; 407-410
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Control of Exciton Fine Structure Splitting in Quantum Dots
Autorzy:
Stevenson, R. M.
Young, R. J.
Atkinson, P.
Cooper, K.
Ritchie, D. A.
Shields, A. J.
Powiązania:
https://bibliotekanauki.pl/articles/2046985.pdf
Data publikacji:
2006-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
03.67.Mn
78.67.Hc
78.55.Cr
Opis:
Quantum dots have been identified as potential sources of entangled photon pairs, essential for many applications in quantum information. However, in practice structural properties of the dots result in polarisation splitting of the emission lines, which has prevented the realisation of such a source. Here, we present two techniques developed to control the polarisation splitting in a quantum dot both irreversibly and reversibly. We find that the splitting is strongly dependent upon the emission energy, or lateral confinement, of the quantum dot. Thus by precise control of the InAs deposition thickness, it is possible to produce ensembles from which dots with zero polarisation splitting can be easily selected. Additionally, we demonstrate that by using modest in-plane magnetic fields to partially mix the bright and dark exciton states, the polarisation splitting can be reversibly tuned to zero for most dots of a certain type. Finally, we demonstrate the emission of triggered entangled photon pairs from a quantum dot with approximately zero splitting with fidelity >70%.
Źródło:
Acta Physica Polonica A; 2006, 110, 3; 311-318
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Role of Internal Electric Fields in III-N Quantum Structure
Autorzy:
Perlin, P.
Łepkowski, S. P.
Teisseyre, H.
Suski, T.
Grandjean, N.
Massies, J.
Powiązania:
https://bibliotekanauki.pl/articles/2027477.pdf
Data publikacji:
2001-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.20.Hp
78.55.Cr
78.67.Hc
Opis:
Binary nitrides: of wurtzite GaN, AlN, InN, and their solid solutions represent a family of semiconductors of crucial importance for modern optoelectronics. Strained quantum wells, like GaN/AlGaN and specially InGaN/GaN, form active layers of the light emitters working in green-UV part of the spectrum. The operation of these devices strongly depends on the emission spectra of considered quantum structures which are greatly influenced by the presence of built-in electric fields. The electric field acting via quantum confined Stark effect in the mentioned structures changes the energies and intensity of the emitted light. The effect can lead to the spectral shift of a photo- and electroluminescence by many hundreds of meV. In this review we will briefly cover the influence of internal electric fields on both optical and electrical properties of nitride based heterostructures and quantum wells. We would like to draw reader's attention to the usefulness of high-pressure investigation in the study of electric fields in nitrides and to show how the interpretation of these experiments influences the way we calculate the electric fields in the quantum structures.
Źródło:
Acta Physica Polonica A; 2001, 100, 2; 261-270
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
CdSe/ZnS Colloidal Quantum Dots with Alloyed Core/Shell Interfaces: A Photoluminescence Dynamics Study
Autorzy:
Dziatkowski, K.
Ratchford, D.
Hartsfield, T.
Li, X.
Gao, Y.
Tang, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1492859.pdf
Data publikacji:
2011-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.47.jd
78.55.Et
Opis:
Time-resolved photon counting technique was employed to study dynamics of photoluminescence from the ensemble and single CdSe/ZnS quantum dots with the alloyed core/shell interfaces. The ensemble data revealed enhanced effect of disorder-induced trap states for increasing emission energy, as implied from the changes in the distribution of total decay rates. The emission trajectories collected for single quantum dots showed familiar, two-state blinking pattern. It suggests that in a large-band-offset CdSe/ZnS system, the introduced alloying of the core-to-shell region cannot smooth enough the confinement potential in order to suppress nonradiative Auger recombination and blinking.
Źródło:
Acta Physica Polonica A; 2011, 120, 5; 870-873
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Long Decays of Excitonic Photoluminescence from CdTe/ZnTe Individual Quantum Dots
Autorzy:
Piechal, B.
Suffczyński, J.
Trajnerowicz, A.
Goryca, M.
Kossacki, P.
Golnik, A.
Gaj, J. A.
Powiązania:
https://bibliotekanauki.pl/articles/2044525.pdf
Data publikacji:
2005-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.47.+p
78.67.Hc
78.55.Et
Opis:
We present time-resolved micro-photoluminescence study of self-assembled CdTe/ZnTe quantum dots. In addition to the fast radiative decay of the exciton, we observe long components, being of the order of a few nanoseconds. We observe that long decays are present for neutral exciton lines as well as on the biexciton ones. The temperature dependent measurements reveal the non-monotonic behaviour. We find also that the long decays are not mono-exponential. We conclude that the dark exciton states cannot be treated as the only source of long decays in the luminescence. We propose other possible explanation, which is the slowing of luminescence by carrier trapping in high energy states in quantum dots and barriers.
Źródło:
Acta Physica Polonica A; 2005, 108, 5; 831-836
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Epitaxial Growth and Optical Properties of PbTe/CdTe Semiconductor Heterostructures
Autorzy:
Szot, M.
Kowalczyk, L.
Smajek, E.
Domukhovski, V.
Domagała, J.
Łusakowska, E.
Taliashvili, B.
Dziawa, P.
Knoff, W.
Wiater, M.
Wojtowicz, T.
Story, T.
Powiązania:
https://bibliotekanauki.pl/articles/1811996.pdf
Data publikacji:
2008-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.55.Hx
78.67.De
78.67.Hc
78.67.Pt
Opis:
Growth optimization, optical and structural properties of PbTe/CdTe multilayers grown by molecular beam epitaxy on GaAs (001) as well as on $BaF_2$ (111) substrates is reported. An intense photoluminescence in the mid-infrared region is observed from PbTe quantum wells excited with 1.17 eV pulsed YAG:Nd laser. The energy of the emission peak shows blue shift with decreasing PbTe well width and has a positive temperature coefficient. The influence of thermal annealing on photoluminescence spectra of PbTe/CdTe multilayers grown on $BaF_2$ substrate is discussed.
Źródło:
Acta Physica Polonica A; 2008, 114, 5; 1391-1396
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Collective Encoding of Quantum Information in a Quantum Dot Register
Autorzy:
Grodecka, A.
Machnikowski, P.
Powiązania:
https://bibliotekanauki.pl/articles/2046914.pdf
Data publikacji:
2006-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
63.20.Kr
03.67.Pp
Opis:
We define the collective logical quantum bit as a state on an array of 2, 4, and 8 quantum dots. We show that such an array can be controlled with less phonon-induced pure dephasing than a single dot. We calculate the dephasing accompanying a single-qubit operation on the collective logical qubit by means of perturbative method describing the open system evolution under arbitrary driving.
Źródło:
Acta Physica Polonica A; 2006, 110, 2; 195-200
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Carrier Dynamics and Dynamic Band-Bending in Type-II ZnTe/ZnSe Quantum Dots
Autorzy:
Syperek, M.
Misiewicz, J.
Chan, C.
Dumcenco, D.
Huang, Y.
Chou, W.
Powiązania:
https://bibliotekanauki.pl/articles/1399095.pdf
Data publikacji:
2013-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Et
78.47.J-
Opis:
Carrier dynamics and dynamic band-bending in self-assembled ZnTe/ZnSe quantum dots have been studied by means of time-resolved photoluminescence experiment at low temperatures. The experiment reveals clearly type-II character of the confinement potential in the dot manifested in: (i) long photoluminescence decay time constant of 28-35 ns, and (ii) temporal shift of the quantum dot peak emission towards low energy following the laser pulse excitation. The magnitude of the spectral shift Δ E depends on the dot size and the power density of excitation pulse. For the dots under study and given experimental conditions Δ E ≈ 28 ÷ 42 meV.
Źródło:
Acta Physica Polonica A; 2013, 124, 5; 821-823
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optically Detected Microwave Resonance and Carrier Dynamics in InAs/GaAs Quantum Dots
Autorzy:
Žurauskienė, N.
Marcinkevičius, S.
Janssen, G.
Goovaerts, E.
Nötzel, R.
Koenraad, P.
Wolter, J.
Powiązania:
https://bibliotekanauki.pl/articles/1178362.pdf
Data publikacji:
2005-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.47.+p
76.70.Hb
Opis:
The properties of small-sized high density InAs/GaAs quantum dots (emitting at 1.25 eV) are studied by means of optically detected microwave resonance spectroscopy and time resolved photoluminescence techniques. The results are discussed in terms of trapping and thermal escape of the carriers as well as their relaxation and recombination in quantum dots. The data are compared with those recently obtained on shallowly formed InAs quantum dot structures.
Źródło:
Acta Physica Polonica A; 2005, 107, 2; 435-439
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of dielectric medium anisotropy on the polarization degree of emission from a single quantum dash
Autorzy:
Mrowiński, P.
Tarnowski, K.
Olszewski, J.
Somers, A.
Kamp, M.
Höfling, S.
Reithmaier, J.
Urbańczyk, W.
Misiewicz, J.
Machnikowski, P.
Sęk, G.
Powiązania:
https://bibliotekanauki.pl/articles/1159588.pdf
Data publikacji:
2016-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
71.35.-y
78.55.-m
Opis:
Excitonic emission from single InAs/InGaAlAs/InP quantum dashes has been investigated in the context of degree of linear polarization by post-growth modification of its surrounding dielectric medium. We present optical spectroscopy measurements on a symmetric squared pedestal structures (mesas), and asymmetric rectangular ones oriented parallel or perpendicular to the main in-plane axis of the dashes [1-10]. Polarization resolved microphotoluminescence shows a significant quantitative modification of the degree of linear polarization value from -20% up to 70%. These results have been confronted with calculations of the coupling between the exciton transition dipole moment and electromagnetic field distributed in the vicinity of a quantum dash inside a processed mesa.
Źródło:
Acta Physica Polonica A; 2016, 129, 1a; A-48-A-52
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photoluminescence Dynamics of CdSe Quantum Dot with Single $Mn^{2+}$ Ion under Modulated Excitation
Autorzy:
Pilat, M.
Goryca, M.
Smoleński, T.
Pacuski, W.
Kossacki, P.
Powiązania:
https://bibliotekanauki.pl/articles/1377238.pdf
Data publikacji:
2014-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.75.Jn
78.47.jd
78.67.Hc
Opis:
A quantum dot with a single magnetic ion is a perfect model system to investigate spin dynamics of a magnetic ion embedded in semiconductor matrix. In this work we present results of spin dynamics studies of $Mn^{2+}$ ion embedded in CdSe quantum dot, performed under modulated excitation of the dot. In particular, the relaxation time of the $Mn^{2+}$ ion in high magnetic field was determined.
Źródło:
Acta Physica Polonica A; 2014, 126, 5; 1212-1214
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Neutral and Charged Excitons Localized in the InAs/GaAs Wetting Layer
Autorzy:
Babiński, A.
Czyż, M.
Golnik, A.
Borysiuk, J.
Kret, S.
Raymond, S.
Lapointe, J.
Wasilewski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1811914.pdf
Data publikacji:
2008-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.21.La
78.55.Cr
78.67.Hc
Opis:
It has recently been shown that potential fluctuations in a wetting layer, which accompanies InAs/GaAs quantum dots can localize excitons. Neutral excitons and biexcitons and charged excitons were identified. In this communication we report on studies of properties of the excitons over wide temperature range (T < 70 K). The micro-photoluminescence measurements enable investigation of excitons localized in a single potential fluctuation. Temperature-induced broadening of the neutral exciton as well as a quenching of the charged exciton at temperatures higher than 50 K are observed and discussed.
Źródło:
Acta Physica Polonica A; 2008, 114, 5; 1055-1060
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Femtosecond Spectral Hole Burning Spectroscopy as a Probe of Exciton Dynamics in Quantum Dots
Autorzy:
Műller, T.
Moldaschl, T.
Parz, W.
Golka, S.
Strasser, G.
Unterrainer, K.
Powiązania:
https://bibliotekanauki.pl/articles/1813185.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.21.La
78.47.-p
78.67.Hc
Opis:
We present measurements of the dynamics of photoexcited excitons in an ensemble of InAs/GaAs self-assembled quantum dots using a femtosecond spectral hole burning technique. We use this technique to examine the exciton spin relaxation and the line shape of optical transitions in the dots.
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 777-782
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Light Emission from CdS Quantum Dots Stabilized by Sugars
Autorzy:
Sergiel, I.
Mirończyk, A.
Kozioł, J.
Defort, A.
Powiązania:
https://bibliotekanauki.pl/articles/1807562.pdf
Data publikacji:
2009-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.21.La
78.67.Hc
78.55.Et
Opis:
CdS nanoparticles were successfully synthesized using starch, amylopectin and maltodextrin, as a capping agent. Optical properties of the final products have been investigated by photoluminescence spectroscopy and Raman scattering. The atomic force microscopy gave a particle of an average size of approximately 6 nm. Our research reveals that all prepared sugar-quantum dot aqueous solutions were stable against precipitation during the time of their investigation and kept their stability for several months after it.
Źródło:
Acta Physica Polonica A; 2009, 116, S; S-166-S-168
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical Properties of Multi-Stacked InAs Quantum Dots Embedded in GaAs/InGaAs Strained Layer and its Annealing Behaviors
Autorzy:
Kim, D.
Kim, G.
Jeon, S.
Cho, M.
Choi, H.
Kim, M.
Lee, D.
Kim, J.
Eom, G.
Leem, J.
Powiązania:
https://bibliotekanauki.pl/articles/1537752.pdf
Data publikacji:
2010-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
78.55.Cr
81.05.Ea
Opis:
Multi-stacked InAs QDs embedded in ten periods of GaAs/$In_{0.1}Ga_{0.9}As$ strained layers were grown by MBE and their optical properties were investigated by using PL spectroscopy. For the QDs embedded in ten periods of GaAs/$In_{0.1}Ga_{0.9}As$ strained layers, the PL intensity is enhanced about 4.7 times and a narrower FWHM of 26 meV is observed compared to those of the conventional multi-stacked QDs. The PL spectra of the InAs QDs show blue-shifts of about 50 meV with increasing annealing temperature up to 850°C. At annealing temperature of 600°C, the FWHM of the PL peak is reduced to 16 meV and PL intensity is enhanced compared to those of the as-grown sample, which indicates improvement of size uniformity and crystal quality of the QDs.
Źródło:
Acta Physica Polonica A; 2010, 117, 6; 941-944
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-50 z 109

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies