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Tytuł:
Frequency Discrimination for Amplitude Modulated Sinusoidal Signals at High Carrier Frequencies
Autorzy:
Sęk, A.
Kordus, M.
Powiązania:
https://bibliotekanauki.pl/articles/1359956.pdf
Data publikacji:
2014-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.66.Fe
43.66.Hg
Opis:
The current study is a continuation of experiments presented by Sęk and Bukała (Acta Physica Polonica A 123, 1106 (2013)). The purpose of the present study was to investigate frequency discrimination of amplitude modulated high frequency carriers. Using 2AFC procedure, the subjects were presented with two observation intervals of which the first interval contained four pulses of the same high frequency signal (called SSSS), while in the second interval (called SHSH) the second and fourth pulses had higher frequencies values (i.e. shifted upwards by Δ f). The carrier frequency (in S pulses) was fixed and equal to 10 kHz. Modulation rates were equal to 100, 200, 337, 500, 600, 733, and 800 Hz. The value of the modulation rate was limited to keep all components of the sinusoidal modulation within one auditory filter (17% of the center frequency) centered at the carrier frequency. Two different types of modulation were used: a simple sinusoidal modulation with the modulation depth m set to 100%, and a logarithmic modulation with the modulation depth m set to 50 dB. Results indicate a strong relationship between frequency discrimination threshold and modulation type. The thresholds are significantly higher for logarithmic modulation in comparison to sinusoidal modulation. Amplitude modulation as well as logarithmic modulation applied to the high frequency carrier cause significant increase in the frequency discrimination threshold. For high frequency sinusoidal signal carriers (i.e. close to 10 kHz), frequency discrimination thresholds do not depend on amplitude modulation rates up to about 800 Hz. In general, the excitation pattern mechanism was a primary cue enabling frequency discrimination of modulated and unmodulated signals to compare with the mechanism based on the temporal fine structure. However, the excitation pattern was not the only mechanism responsible for the frequency discrimination.
Źródło:
Acta Physica Polonica A; 2014, 125, 4A; A-149-A-154
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Use of the Phase Locking Information in the Human Auditory System for Frequencies Above 5 kHz
Autorzy:
Sęk, A.
Bukała, M.
Powiązania:
https://bibliotekanauki.pl/articles/1400102.pdf
Data publikacji:
2013-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.66.Fe
43.66.Hg
Opis:
Accurate allocation of neural impulses to the same phase (i.e. phase locking) in the auditory system, ceases for frequencies above 5 kHz. However, some recent works suggest that it may have a much higher value. A discrimination of harmonic complex and inharmonic complex sound, formed using sound harmonic complex, in which all components were shifted towards higher frequency by the same number in hertzs, was analyzed. Fundamental frequency was $F_0$=1 kHz and signals were bandpass filtered by a fixed filter center frequency of which was $11F_0$ and bandwidth $5F_0$. Discrimination threshold was $\Delta F=0.089F_0$ for 10 normal-hearing subjects. However, replacing the sinusoidal components with the noise bands brought about a significant increase in thresholds. The largest increase was observed for 700 Hz bandwidth. The replacement of sinusoidal components with noisebands reduces information conveyed by phase locking. The differences in excitation pattern for harmonic complex and inharmonic complex signals, for the average threshold, did not exceed 0.7 dB. Therefore they could not be a useful cue for harmonic complex and inharmonic complex discrimination. A simplified model of phase locking showed that the substitution of sinusoids with bands of noise significantly reduced number of intervals between successive neural spikes corresponding to the virtual pitch of harmonic complex and inharmonic complex sounds. This degradation of discrimination suggests that the main source of information about the pitch of harmonic complex and inharmonic complex, especially for sinusoidal components, was the phase locking.
Źródło:
Acta Physica Polonica A; 2013, 123, 6; 1106-1113
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Convolutive Blind Signal Separation Spatial Effectiveness in Speech Intelligibility Improvement
Autorzy:
Kociński, J.
Sęk, A.
Libiszewski, P.
Powiązania:
https://bibliotekanauki.pl/articles/1504381.pdf
Data publikacji:
2011-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
43.72.-p
43.60.-c
43.60.+d
Opis:
Blind signal separation is one of the latest methods to improve the signal to noise ratio. The main objective of blind source separation is the transformation of mixtures of recorded signals to obtain each source signal at the output of the procedure, assuming that they are statistically independent. For acoustic signals it can be concluded that the correct separation is possible only if the source signals are spatially separated. That finding suggests analogies with the classical spatial filtering (beamforming). In this study we analyzed an effect of the angular separation of two source signals (i.e. speech and babble noise) to improve speech intelligibility. For this purpose, we chose the blind source separation algorithm based on the convolutive separation, based on second order statistics only. As a system of sensors a dummy head was used (one microphone inside each ear canal), which simulated two hearing aids of a hearing impaired person. The speech reception threshold, before and after the blind source separation was determined. The results have shown significant improvement in speech intelligibility after applying blind source separation (speach reception threshold fell even more than a dozen dB) in cases where the source signals were angularly separated. However, in cases where the source signals were coming from the same directions, the improvement was not observed. Moreover, the effectiveness of the blind source separation, to a large extent, depended on the relative positions of signal sources in space.
Źródło:
Acta Physica Polonica A; 2011, 119, 6A; 996-999
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical Trapping and Propagation of Nonresonantly Driven One-Dimensional Exciton-Polariton Condensate
Autorzy:
Opala, A.
Pieczarka, M.
Sęk, G.
Powiązania:
https://bibliotekanauki.pl/articles/1033879.pdf
Data publikacji:
2017-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
67.85.De
71.36.+c
03.75.Kk
Opis:
We study theoretically a nonresonant optical creation of a one-dimensional exciton-polariton condensate in a semiconductor microcavity. The polariton condensate is treated in the mean-field approach, taking into consideration an antitrapping potential created by the reservoir of noncondensed particles. Polariton condensates are excited by multiple lasers, with a combination of continuous wave and pulsed sources. The proposed pump-probe configuration leads to the realisation of various experimental schemes, e.g. optical trapping of a polariton condensate in real space. Moreover, it can be utilised for investigation of elementary excitations in the time domain when polariton condensates from two sources interact with each other.
Źródło:
Acta Physica Polonica A; 2017, 132, 2; 401-404
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:
Electronic Structure of Elongated $In_{0.3}Ga_{0.7}As//GaAs$ Quantum Dots
Autorzy:
Pieczarka, M.
Musiał, A.
Podemski, P.
Sęk, G.
Misiewicz, J.
Powiązania:
https://bibliotekanauki.pl/articles/1399091.pdf
Data publikacji:
2013-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
73.21.La
73.22.-f
Opis:
In this contribution the electronic structure of large $In_{0.3}Ga_{0.7}As//GaAs$ quantum dots is studied theoretically by means of 8 band k · p modeling. These quantum dots constitute unique physical system due to the low strain limit of the Stranski-Krastanow growth mode resulting in relatively large physical volume and elongation of the quantum dots in [1-10] direction. As a result of these critical growth conditions the electronic structure is expected to be very sensitive to the nanostructure size, shape, and composition of the quantum dot as well as the accompanying wetting layer. Another peculiarity of investigated system is the confining potential which is rather shallow and weakened in comparison to standard quantum dots. It makes them very interesting in view of both fundamental study and potential applications. To reveal physical mechanisms determining the optical properties of the investigated system, the electronic structure, mainly the number of confined states, and the wave function extension as a function of both quantum dot size and geometry have been simulated numerically and the importance of electron-hole Coulomb interactions has been evaluated.
Źródło:
Acta Physica Polonica A; 2013, 124, 5; 809-812
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Confinement Anisotropy on Excitonic Properties in InAs/InP Quantum Dashes
Autorzy:
Mrowiński, P.
Musiał, A.
Sęk, G.
Misiewicz, J.
Höfling, S.
Somers, A.
Hein, S.
Forchel, A.
Powiązania:
https://bibliotekanauki.pl/articles/1399087.pdf
Data publikacji:
2013-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.35.-y
71.70.Gm
78.67.Hc
73.21.-b
81.07.Ta
Opis:
The influence of confinement potential anisotropy on emission properties of strongly elongated single InAs/InGaAlAs/InP quantum dashes has been investigated by polarization-resolved microphotoluminescence spectroscopy at around 1.5 μm. There have been determined the exciton fine structure splitting, degree of linear polarization of surface emission and biexciton binding energy. The investigated dashes exhibited usually: the exciton anisotropy splitting larger than 100 μeV, the corresponding biexciton binding energy of about 3 meV, and the degree of linear polarization values in the range from 24% to 55%. Here, we presented a correlation of these parameters for several quantum dashes, which can be attributed either to a change in lateral aspect ratio within the ensemble, or the carrier localization on random fluctuations of the dash confinement potential.
Źródło:
Acta Physica Polonica A; 2013, 124, 5; 801-804
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical, Structural, and Electrical Properties of Aromatic Triphenylamine-Based Poly(azomethine)s in Thin Layers
Autorzy:
Palewicz, M.
Iwan, A.
Sikora, A.
Doskocz, J.
Strek, W.
Sek, D.
Mazurek, B.
Powiązania:
https://bibliotekanauki.pl/articles/1490096.pdf
Data publikacji:
2012-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
77.84.Jd
73.61.Ph
78.66.Qn
Opis:
Spectroscopic and photophysical properties of the poly(azomethine)s with triphenylamine moieties were investigated by UV-vis, X-ray diffraction and atomic force microscopy methods. Current-voltage measurements were performed on ITO/polymer/$Alq_3$/Al, ITO/PEDOT/polymer:MWCNT/Al and ITO/polymer:MWCNT/Al devices. Multiwall carbon nanotubes were blended with polymer in the ratio 1:1. The lowest optical band gap value at 2.33 eV was detected. Moreover, an absorption coefficient α was calculated from transmission and reflectivity measurements. In this paper, we presented photophysical and structural properties of the poly(azomethine)s in solid state of great interest for the emerging field of molecular electronics and for their uses as active layers in (opto)electronic devices such as solar cells.
Źródło:
Acta Physica Polonica A; 2012, 121, 2; 439-444
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Built-in Electric Field on Forbidden Transitions in In_xGa$\text{}_{1-x}$As/GaAs Double Quantum Well by Three-Beam Photoreflectance
Autorzy:
Sęk, G.
Ryczko, K.
Misiewicz, J.
Bayer, M.
Wang, T.
Forchel, A.
Powiązania:
https://bibliotekanauki.pl/articles/2028844.pdf
Data publikacji:
2001-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.-r
78.66.-w
Opis:
Photoreflectance spectroscopy has been used to study optical transitions in In$\text{}_{0.045}$Ga$\text{}_{0.955}$As/GaAs double quantum well at 80 K. The derivative nature of this contactless electromodulation technique allows for the observation of excited state transitions in the low-dimensional structure including the symmetry-forbidden ones. Excitonic symmetry-forbidden transitions can be observed due to the effect of mixing of heavy and light hole excitons and/or due to some asymmetry in the structure. We have shown that the built-in electric field in the region of double quantum well is weak enough (less than 0.5 kV/cm) not to cause any significant energetic shift of features due to quantum confined Stark effect, on one hand. On the other hand, it is sufficient to change strongly the oscillator strength of forbidden transitions. To change the internal electric field, we have used photoreflectance in the three-beam mode with a third beam continuously illuminating the sample and causing changes of the built-in electric fields due to the photovoltage effect. This method works as a contactless forward bias and allows for a change of the field down to the flat band conditions. We have shown that changes of built-in electric field by amount of a few tenths of kV/cm can modify the intensity of forbidden transitions significantly. We show that, although the mixing of excitons is still important, a very weak built-in electric field can be dominant in the observation of forbidden excitonic transitions in double quantum well.
Źródło:
Acta Physica Polonica A; 2001, 100, 3; 417-424
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:
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:
InAs on InP Quantum Dashes as Single Photon Emitters at the Second Telecommunication Window: Optical, Kinetic, and Excitonic Properties
Autorzy:
Mrowiński, P.
Dusanowski, Ł.
Somers, A.
Höfling, S.
Reithmaier, J.
Misiewicz, J.
Sęk, G.
Powiązania:
https://bibliotekanauki.pl/articles/1033861.pdf
Data publikacji:
2017-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
photoluminescence
quantum dash
excitonic complexes
antibunching
autocorrelation
single photon source
telecommunication
time-resolved
Opis:
In this work, InAs/InGaAlAs/InP quantum dashes have been investigated in terms of their optical, kinetic, and excitonic properties with respect to their application within the 1300± 40 nm spectral range, i.e. the O-band of the telecommunication technologies. We focused on the basic excitonic complexes such as neutral exciton, biexciton, and charged exciton, which have been identified by means of photoluminescence measurements. Emission and carriers' dynamics have been analyzed using rate equation model and fitting the experimental data obtained for both continuous-wave and pulsed excitation regimes. There has been found a significant impact of the charge carrier imbalance in the system and electron capturing rate on the dynamics of the optical and electronic transitions, which results in a high occupation of the negatively charged trion state. Autocorrelation measurements show clear antibunching of trion emission for non-resonant excitation which indicates a potential of such kind of emitters as single photon sources for short-range quantum communication schemes.
Źródło:
Acta Physica Polonica A; 2017, 132, 2; 382-386
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Energy Transfer Processes in InAs/GaAs Quantum Dot Bilayer Structure
Autorzy:
Pieczarka, M.
Maryński, A.
Podemski, P.
Misiewicz, J.
Spencer, P.
Murray, R.
Sęk, G.
Powiązania:
https://bibliotekanauki.pl/articles/1185237.pdf
Data publikacji:
2016-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.67.Hc
71.35.-y
78.55.-m
Opis:
We investigate double layer InAs/GaAs quantum dots grown in the Stransky-Krastanov mode by molecular beam epitaxy. The sample consists of two layers of InAs quantum dots separated by 10 nm thick GaAs layer, where the top quantum dot layer of an improved homogeneity is covered by an InGaAs cap. This configuration has allowed for the extension of the dots' emission to longer wavelengths. We probed the carrier transfer between the states confined in a double quantum well composed of InGaAs cap and the quantum dots wetting layer to the states in the quantum dots by means of photoluminescence excitation and photoreflectance spectroscopies. Efficient emission from quantum dots excited at the double quantum well ground state energy was observed. There is also presented a discussion on the carrier injection efficiency from the capping layer to the quantum dots.
Źródło:
Acta Physica Polonica A; 2016, 129, 1a; A-59-A-61
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
GaAs-Based Quantum Well Exciton-Polaritons beyond 1 μm
Autorzy:
Pieczarka, M.
Podemski, P.
Musiał, A.
Ryczko, K.
Sęk, G.
Misiewicz, J.
Langer, F.
Höfling, S.
Kamp, M.
Forchel, A.
Powiązania:
https://bibliotekanauki.pl/articles/1399094.pdf
Data publikacji:
2013-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.21.-b
78.67.-n
78.67.Pt
Opis:
Realization of the Bose-Einstein condensate can provide a way for creation of an inversion-free coherent light emitter with ultra-low threshold power. The currently considered solutions provide polaritonic emitters in a spectral range far below 1 μm limiting their application potential. Hereby, we present optical studies of InGaAs/GaAs based quantum well in a cavity structure exhibiting polaritonic eigenmodes from 5 to 160 K at a record wavelength exceeding 1 μm. The obtained Rabi splitting of 7 meV was almost constant with temperature, and the resulting coupling constant is close to the calculated QW exciton binding energy. This indicates the very strong coupling conditions explaining the observation of polaritons at temperatures where the exciton dissociation is already expected, and allows predicting that room temperature polaritons could still be formed in this kind of a system.
Źródło:
Acta Physica Polonica A; 2013, 124, 5; 817-820
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimizing the InGaAs/GaAs quantum dots for 1.3 μm emission
Autorzy:
Maryński, A.
Mrowiński, P.
Ryczko, K.
Podemski, P.
Gawarecki, K.
Musiał, A.
Misiewicz, J.
Quandt, D.
Strittmatter, A.
Rodt, S.
Reitzenstein, S.
Sęk, G.
Powiązania:
https://bibliotekanauki.pl/articles/1055140.pdf
Data publikacji:
2017-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.30.Fs
78.67.-n
78.67.Hc
73.22.-f
Opis:
Hereby we present comprehensive experimental and theoretical study on fundamental optical properties and electronic structure of GaAs-based quantum dots grown using metalorganic chemical vapor deposition technique. The substantial redshift of emission, to the second telecommunication window of 1.3 μm, in comparison to standard InGaAs/GaAs quantum dots is obtained via strain engineering utilizing additional capping layer of In_{0.2}Ga_{0.8}As in this context referred to as strain reducing layer. It ensures lowering of the energy of the ground state transition to more application relevant spectral range. Optical properties of the quantum dot structure has been experimentally characterized by means of photoreflectance spectroscopy and power-dependent photoluminescence revealing 3 transitions originating from hybrid states confined in an asymmetric double quantum well formed of the wetting layer and strain reducing layer, as well as higher states of the quantum dots themselves with the first excited state transition separated by 67 meV from the ground state transition. Origin of the observed transitions was confirmed in theoretical modelling using 1-band single-particle approach for the quantum well part, and excitonic quantum dot spectrum obtained within 8 band k·p formalism followed by configuration interaction calculations, respectively. Additionally, photoluminescence excitation spectroscopy measurements allowed to identify a spectral range for efficient quasi-resonant excitation of the investigated quantum dots into the 2D density of states to be in the range of 835-905 nm.
Źródło:
Acta Physica Polonica A; 2017, 132, 2; 386-390
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
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