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 "73.20.Dx" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-50 z 109
Tytuł:
Wigner Crystallization in InGaAs/InP Heterostructures with a Strong Disorder
Autorzy:
Kovács, Gy.
Remenyi, G.
Gombos, G.
Savel'ev, I. G.
Kreshchuk, A. M.
Hegman, N.
Pödör, B.
Powiązania:
https://bibliotekanauki.pl/articles/1933825.pdf
Data publikacji:
1995-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
Non-linear current-voltage characteristics were observed in the range of filling factors of 0.3 ≤ v ≤ 0.4 in a two-dimensional electron system in InGaAs/InP heterostructures with a strong disorder. The observations are explained qualitatively in terms of magnetic field induced localization and Wigner solidification.
Źródło:
Acta Physica Polonica A; 1995, 88, 4; 783-786
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spontaneous Persistent Currents in Mesoscopic Rings
Autorzy:
Zipper, E.
Szopa, M.
Powiązania:
https://bibliotekanauki.pl/articles/1931872.pdf
Data publikacji:
1995-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
Persistent currents in mesoscopic systems made of a very clean metal and with nearly flat Fermi surface are studied. It is shown that the inclusion of the orbital magnetic interaction between electrons can lead to spontaneous currents (spontaneous fluxes) and to quantized flux trapping if the number of interacting electrons is large enough: The energy of the system is discussed and the self-consistent formulas for the spontaneous flux and for the quantized flux in the system is derived. The influence of the spin on the presented phenomena is discussed.
Źródło:
Acta Physica Polonica A; 1995, 87, 1; 79-84
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electrical and Optical Characterization of Nanostructures
Autorzy:
Gornik, E.
Smoliner, J.
Rosskopf, V.
Powiązania:
https://bibliotekanauki.pl/articles/1931909.pdf
Data publikacji:
1995-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
The characterization of nanostructures is a topic of vital interest, since the dimensions of commercially available semiconductor devices are now in a range, where quantum size effects become evident. In this paper, various methods are presented to characterize low-dimensional structures. Magnetic depopulation, tunneling, far infrared transmission, photo-conductivity and magnetophonon resonances are used to determine the low-dimensional sub-band energies. For each method, the special features are discussed and it is demonstrated that the different methods yield different, complementary information.
Źródło:
Acta Physica Polonica A; 1995, 87, 1; 119-131
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Model of the Electron Transport in a Quantum Wire with Contacts
Autorzy:
Jungwirth, T.
Powiązania:
https://bibliotekanauki.pl/articles/1924221.pdf
Data publikacji:
1992-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
A new model of the electron transport in a quantum wire with contacts is presented. The contact between the reservoir and the quantum past of the system is assumed to be lengthwise the ideal lead. The equilibrium state of electrons in the reservoir gives the final distribution of a non-equilibrium electron system in the ideal lead. The model enables a continuous quasi-1D description of the electron transport evoked by a difference of chemical potentials as well as by a difference of temperatures of reservoirs.
Źródło:
Acta Physica Polonica A; 1992, 82, 5; 882-886
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model of Qubit in Multi-Electron Quantum Dot
Autorzy:
Jacak, L.
Krasnyj, J.
Jacak, D.
Salejda, W.
Mituś, A.
Powiązania:
https://bibliotekanauki.pl/articles/2024044.pdf
Data publikacji:
2001-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
The discussion of qubit for quantum computation in quantum dots technology is presented. The state-of-the-art structure of multi-electron dot is considered and the appropriate quasi-two-level system is suggested employing the singlet-triplet transition in the presence of magnetic field. The methods of qubit rotation (the write procedure) as well as two-qubit operations, as controlled-NOT, in vertically stacked dots system are analysed.
Źródło:
Acta Physica Polonica A; 2001, 99, 2; 277-291
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Activated Transport in Magnetic-Field Induced Insulating Phase in Two-Dimensional Electron Gas in InGaAs/InP Heterostructures
Autorzy:
Pődör, B.
Gombos, G.
Reményi, G.
Kovács, Gy.
Savel'ev, I. G.
Novikov, S. V.
Powiązania:
https://bibliotekanauki.pl/articles/1968409.pdf
Data publikacji:
1997-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
We report on experiments on low temperature (millikelvin range) activated magnetotransport on low-density two-dimensional electron systems in InGaAs/InP for Landau level filling factors 0.25 ≤ ν ≤ 0.55. The activation energy increases approximately linearly with decreasing filling factor. The observations are discussed in the light of the formation of the Wigner solid.
Źródło:
Acta Physica Polonica A; 1997, 92, 5; 945-949
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Resonant Subband-Landau Level Coupling in Systems with Anisotropic and Tilted Valleys
Autorzy:
Zalużny, M.
Okulski, W.
Powiązania:
https://bibliotekanauki.pl/articles/1890833.pdf
Data publikacji:
1991-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
The problem of the anticrossing of the Landau levels originating from the ground subband and first excited subband in the quasi-two-dimensional systems with anisotropic valleys in the presence of the tilted magnetic field is discussed in the framework of the perturbation theory. The full field coupling regime is considered. Comparison with the existing theoretical and experimental results is given.
Źródło:
Acta Physica Polonica A; 1991, 80, 3; 337-340
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Formation Energy and Electronic Structure of II-VI/IV Semiconductor Superlattices
Autorzy:
Jędrzejek, C.
Konior, J.
Kaprzyk, S.
Powiązania:
https://bibliotekanauki.pl/articles/1872700.pdf
Data publikacji:
1995-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
We calculate formation energy and electronic structure of ultrathin (001)II-VI/IV semiconductor superlattices using the Korringa-Kohn-Rostoker all-electron method. Formation energies (∆H) are 2.18 eV for (Ge$\text{}_{2}$)$\text{}_{1}$(ZnSe)$\text{}_{1}$ and 1.50 eV for (ZnS)$\text{}_{1}$(Si$\text{}_{2}$)$\text{}_{1}$. The results of this work are significantly different from these by Ferraz and Srivastava who obtained ∆H = 0.88 eV for (001)(Ge$\text{}_{2}$)$\text{}_{1}$(ZnSe)$\text{}_{1}$ and moreover the one-layer super-lattices are metallic, which confirms the results by Ohno and Ito. The large formation energies surely lead to interfacial instability.
Źródło:
Acta Physica Polonica A; 1995, 87, 2; 349-352
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Physics of Resonant Tunnelling
Autorzy:
Sheard, F. W.
Fromhold, T. M.
Powiązania:
https://bibliotekanauki.pl/articles/1920955.pdf
Data publikacji:
1992-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
A description is given of resonant tunnelling processes in double-barrier semiconductor heterostructures from the point of view of sequential theory. If a magnetic field is applied in the plane of the barrier interfaces, the energy and transverse momentum of the electrons injected into the quantum well through the emitter tunnel barrier can be varied independently by changing the applied voltage and magnetic field. This technique can be used to probe the energy and momentum spectrum of the subband states in a quantum well. In n-type wide-well structures, a detailed interpretation of magneto-oscillations in the tunnel current has been given in terms of semiclassical orbits of electrons in the well. In p-type structures with narrow wells, the dispersion curves of hole subbands, which are complicated by the strong mixing of light hole and heavy hole states, have been directly studied. Resonant tunnelling into the bound state of single donor atoms in a quantum well has recently been observed. The magnetic field dependence of the tunnel current then gives a measure of the transverse momentum distribution and hence lateral extent of the donor wave function.
Źródło:
Acta Physica Polonica A; 1992, 82, 4; 523-538
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Interband Absorption in InGaAs/GaAs Quantum Well at High Hydrostatic Pressure
Autorzy:
Sosin, T. P.
Perlin, P.
Trzeciakowski, W.
Tober, R.
Powiązania:
https://bibliotekanauki.pl/articles/1929745.pdf
Data publikacji:
1993-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
The interband absorption of strained InGaAs/GaAs multiple quantum well was studied at room temperature for pressures up to 5.5 GPa. Three absorption lines were attributed to the excitonic transitions hh1-e1, lh1-e1 and hh2-e2. They were visible until pressure of about 5 GPa which is above the Γ-X crossover for this system. Pressure coefficients of the observed lines were compared with the literature data. The origin of broadening of the lines above Γ-X crossover is discussed.
Źródło:
Acta Physica Polonica A; 1993, 84, 4; 749-752
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Solid State Quantum Interferometers (with and without the Warts)
Autorzy:
Washburn, S.
Powiązania:
https://bibliotekanauki.pl/articles/1931867.pdf
Data publikacji:
1995-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
A brief review of quantum interference in small conductors is followed by a discussion of quantum interference in ballistic conductors. The ballistic conductors are characterized by conservation of the momentum vector and this leads to a simple model for the details of the conductance of the system. In contrast, for diffusive conductors one can only predict the statistical behavior of the interference contributions to the conductance. The response of the ballistic interferometers is governed by semiclassical physics of the electron momentum states (i.e. the modes) in the quantum conductor. Under circumstances of reduced backscattering of the modes, the interference pattern appears to imitate that from a simple optical interferometer. New results from ballistic interferometers are reviewed briefly.
Źródło:
Acta Physica Polonica A; 1995, 87, 1; 57-66
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Many-Electron Effects in Low-Dimensional Semiconductor Structures
Autorzy:
Hawrylak, P.
Powiązania:
https://bibliotekanauki.pl/articles/1931870.pdf
Data publikacji:
1995-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
Many-electron effects in low-dimensional semiconductor structures: quantum wells, wires, and dots are discussed. Three examples are given: (a) the quasi-particles of a Fermi liquid are illustrated with the calculation of the self-energy of a hot electron coupled to plasmons and optical phonons in modulation doped quantum wells, (b) the Fermi edge singularity and (c) the incompressible states of strongly correlated electrons in quantum dots tunable by applied magnetic field.
Źródło:
Acta Physica Polonica A; 1995, 87, 1; 67-77
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Valence Band Quantization in a Spherical Quantum Dot
Autorzy:
Buczko, R.
Powiązania:
https://bibliotekanauki.pl/articles/1923770.pdf
Data publikacji:
1992-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
An analytical solution of the effective mass equation for a spherical valence band in cubic semiconductors is presented. The full degeneracy of the valence band, i.e. the light-hole, heavy-hole and spin-orbit split-off subbands, were taken into account. The analytical wave functions of the valence band were used for its quantization in a completely isolated (infinite potential barrier approximation) quantum dot. The dependence of discrete valence levels on the dot diameter is presented for the CuCl case.
Źródło:
Acta Physica Polonica A; 1992, 82, 5; 789-792
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Unified Approach to Interface and Confined Bulk Optical Phonons in Quantum Wells and Superlattices
Autorzy:
Röseler, J.
Suisky, D.
Powiązania:
https://bibliotekanauki.pl/articles/1924261.pdf
Data publikacji:
1992-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
A unified description of confined optical LO, TO and interface phonons is given on the basis of vector "ghost" fields defined in the whole space. These fields are characterized by the relations for longitudinal and transversal fields. Real displacement fields are obtained by introducing confinement conditions. Interface charges and vortices appear due to this procedure.
Źródło:
Acta Physica Polonica A; 1992, 82, 5; 919-923
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ground-State Structure of a Two-Electron Quantum Dot
Autorzy:
El-Said, M.
Powiązania:
https://bibliotekanauki.pl/articles/2014017.pdf
Data publikacji:
2000-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
The energy spectrum of two interacting electrons, confined in a parabolic quantum dot, presented in a magnetic field is obtained. We have analyzed the energy level crossings between spin-singlet and spin-triplet states. The influence of the quantum dot size on these crossings is also shown. The results of our calculations seem to be in good agreement with analytical and exact numerical data.
Źródło:
Acta Physica Polonica A; 2000, 97, 6; 1023-1032
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical Description of Shell Filling in Cylindrical Quantum Dots
Autorzy:
Szafran, B.
Bednarek, S.
Adamowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1992210.pdf
Data publikacji:
1998-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
A theoretical quantitative description is given for non-periodic oscillations observed in a current vs. gate voltage characteristics of cylindrical quantum dots. Energy eigenvalues and chemical potentials for a system of N confined electrons (N=1,...,13) are calculated by the unrestricted Hartree-Fock method with a confinement potential proportional to the gate voltage. The positions of the observed peaks of the current are reproduced with a very good accuracy. The non-periodicity of the characteristic is explained as a result of the shell filling, which is a signature of the quantum Coulomb blockade.
Źródło:
Acta Physica Polonica A; 1998, 94, 3; 555-559
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Two-Electron Quantum Dots in Magnetic Field
Autorzy:
Adamowski, J.
Spisak, B.
Powiązania:
https://bibliotekanauki.pl/articles/1968005.pdf
Data publikacji:
1997-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
A theoretical description is given for electronic properties of semiconductor quantum dots in a magnetic field. A two-electron model is applied for electrons in a cylindrical quantum dot with a parabolic confinement potential. The eigenvalue problem is solved by the variational method with the trial wave function proposed in the form of linear combination of S-type and P-type Gaussians. The energy levels of singlet and triplet states with arbitrary radial and magnetic quantum numbers have been calculated as a function of the applied magnetic field. The calculated cyclotron transition energies agree well with those measured for InGaAs/GaAs quantum dots. It is shown that the electron-electron interaction has a small influence on the transition energy.
Źródło:
Acta Physica Polonica A; 1997, 92, 4; 695-698
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
InSb/CdTe Heterojuncton: Self-Consistent Calculations of the Energy Structure
Autorzy:
Sobkowicz, P.
Singleton, J.
Greene, S. K.
Powiązania:
https://bibliotekanauki.pl/articles/1891271.pdf
Data publikacji:
1991-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
Results of self-consistent calculations of the subband energy structure of two-dimensional electron gas in the InSb/CdTe heterojunction are reported. Subband occupations and spin splitting in the absence of magnetic field are presented and compared with results of magneto-transport measurements on high mobility, low carrier density heterojunctions.
Źródło:
Acta Physica Polonica A; 1991, 80, 3; 417-420
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Density of Gap States Deconvoluted from Photoconductive Spectra for Undoped Amorphous Silicon and Silicon-Carbon Thin Films
Autorzy:
Pisarkiewicz, T.
Stapiński, T.
Adriaenssens, G.
Lauwerens, W.
Rava, P.
Powiązania:
https://bibliotekanauki.pl/articles/1873043.pdf
Data publikacji:
1995-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
Density of states in amorphous hydrogenated silicon and silicon-carbon thin films were calculated by deconvolution of the optical absorption coefficient a! measured by constant photocurrent method. Addition of carbon to silicon lattice increases the optical band-gap and influences the distribution of defect states in the gap.
Źródło:
Acta Physica Polonica A; 1995, 87, 2; 407-410
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Quantum Magnetotransport in InGaAs/InP at High Magnetic Fields and Low Temperatures
Autorzy:
Kovacs, Gy.
Novikov, V.
Gombos, G.
Podor, B.
Remenyi, Gy.
Powiązania:
https://bibliotekanauki.pl/articles/1876235.pdf
Data publikacji:
1995-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
Opis:
Quantum Hall effect and Shubnikov-de Haas effect measurements were made in two-dimensional electron gas in liquid phase epitaxially grown Ga$\text{}_{0.47}$In$\text{}_{0.53}$As/InP heterostructures in high magnetic fields in the temperature range from 4.2 K down to 60 mK. Two-dimensional electron gas concentrations and mobilities were in the range of (1 - 3) × 10$\text{}^{11}$ cm$\text{}^{-2}$ and (1 - 3) × 10$\text{}^{4}$ cm$\text{}^{2}$/(V s), respectively. Corresponding to this the i = 1 quantum Hall effect plateau occurred at about 6 T magnetic field. Although fractional occupation numbers of about 0.3 were reached, no signs of fractional quantization were detected. Both current and frequency breakdown of the quantum Hall effect were investigated. Narrowing of the plateaus with increasing current differs from that measured in GaAs/AlGaAs structures because of the different mechanisms of dissipation. The fact that the magnetic length becomes smaller than the characteristic scale of the disorder seems to be essential in understanding the low frequency breakdown via the presence of quasi-classical electron states.
Źródło:
Acta Physica Polonica A; 1995, 87, 2; 473-476
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Electric and Magnetic Fields on Donor States in Semiconductor Quantum Wells
Autorzy:
Rolnik, S.
Adamowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1952076.pdf
Data publikacji:
1996-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
73.20.Hb
Opis:
An influence of static external electric and magnetic fields on donor states in a quantum well is studied by variational means. The energies of the 1s and 2p$\text{}_{±}$ hydrogenic states were calculated for different structure parameters (well depth and width) and different fields applied. The calculated 1s-2p$\text{}_{±}$ transition energies agree well with experimental data.
Źródło:
Acta Physica Polonica A; 1996, 90, 5; 915-918
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Calculation of Excitonic Absorption Spectrum of GaAs Quantum Wire Free-Standing in Vacuum
Autorzy:
Vagner, P.
Munzar, D.
Moško, M.
Powiązania:
https://bibliotekanauki.pl/articles/1968439.pdf
Data publikacji:
1997-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.-r
73.20.Dx
Opis:
The electron-hole interaction in a thin (≈10 nm) GaAs quantum wire free-standing in vacuum is strongly enhanced by the image charge due to the abrupt permittivity drop at the wire surface. As a result, the exciton binding energies are much larger and the exciton wave functions much more localised than those of the GaAs quantum wire surrounded by the AlGaAs. The absorption spectrum of the free-standing wire shows besides the 1s exciton peak also the 3s and 5s exciton peaks, even if the peaks are 15 meV broad. The continuum absorption edge shows a large blue shift due to the renormalization of single-particle energies by the image charge.
Źródło:
Acta Physica Polonica A; 1997, 92, 5; 1038-1042
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stark Effect for Donors in Double Quantum Wells
Autorzy:
Rolnik, S.
Adamowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/1933967.pdf
Data publikacji:
1995-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
73.20.Hb
Opis:
The problem of a hydrogenic donor in a semiconductor double quantum well under a homogeneous electric field is studied by variational means. The energy levels corresponding to the quantum states 1s, 2s, 2p have been calculated with the help of the many-element variational basis consisting of the exponential functions. The influence of the electric field on the donor binding energy is determined for different impurity positions. The 1s-2p transition energies have been calculated for a possible comparison with experiment.
Źródło:
Acta Physica Polonica A; 1995, 88, 5; 893-896
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the Transmission Coefficient for the Double δ-Function Potential
Autorzy:
Yanetka, I.
Powiązania:
https://bibliotekanauki.pl/articles/2014026.pdf
Data publikacji:
2000-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.40.Gk
73.20.Dx
Opis:
The unbound-state solution of the Schrödinger equation is examined for the potential that is defined as the sum of two δ'-functions of non-equal strengths. The analytical expression for the transmission coefficient is derived from the solution. The transmission coefficient has an absolute maximum at the zero wave number. Further, the transmission coefficient is shown to exhibit relative maxima and minima. Moreover, it is proved that the transmission coefficient in its relative maxima is larger and in its relative minima is smaller than the transmission coefficient for the corresponding single δ'-function potential.
Źródło:
Acta Physica Polonica A; 2000, 97, 6; 1053-1060
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spin-Orbit-Coupling, Electric-Field and Free-Carrier-Screening Effects on Valence Band Structure of Strained Coupled Quantum Wells
Autorzy:
Olejníková, B.
Powiązania:
https://bibliotekanauki.pl/articles/1968410.pdf
Data publikacji:
1997-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.40.Kp
73.20.Dx
Opis:
We have calculated the structure of the valence bands and its dependence on the electric field and the density of free carriers in a lattice mismatched single and double quantum well. Our calculation is based on simultaneous solving of the effective mass equation for the envelope functions and Poisson's equation. The 6×6 Luttinger-Kohn Hamiltonian is diagonalized into two 3×3 blocks by a unitary transformation. We have shown how including the coupling between spin-orbit split-off band and light- and heavy-hole bands influences the shape of the valence bands. Further it has been found that at high densities of the free carriers and at non-zero electric field, the free-carrier screening affects the valence band structure and wave functions. This effect is considerably pronounced in double quantum well because of large spreading of the quantum states. The studying of the above effects is useful for band-structure engineering.
Źródło:
Acta Physica Polonica A; 1997, 92, 5; 940-944
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Cyclotron-Intersubband Coupling in Periodically Modulated Quasi-Two-Dimensional Electron Gas
Autorzy:
Załużny, M.
Stańko, T.
Powiązania:
https://bibliotekanauki.pl/articles/1968453.pdf
Data publikacji:
1997-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.61.Ey
73.20.Dx
Opis:
The problem of the coupling between the Landau levels originating from the ground and first excited subband in laterally modulated quasi-two-dimensional systems in the presence of the tilted magnetic field is discussed in the framework of the one-electron perturbation theory. It was found that the tilting of the superlattice potential leads to the strong dependence of this coupling on the orientation of the magnetic field with respect to the lateral confinement direction.
Źródło:
Acta Physica Polonica A; 1997, 92, 5; 1072-1074
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of CdTe/Cd$\text{}_{1-x}$Mg$\text{}_{x}$Te Double Barrier, Single Quantum Well Heterostructures for Resonant Tunneling
Autorzy:
Reuscher, G.
Keim, M.
Fischer, F.
Waag, A.
Landwehr, G.
Powiązania:
https://bibliotekanauki.pl/articles/1933964.pdf
Data publikacji:
1995-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
73.61.Ga
Opis:
We report the first observation of resonant tunneling through a CdTe/Cd$\text{}_{1-x}$Mg$\text{}_{x}$Te double barrier, single quantum well heterostructure. Negative differential resistance is observable at temperatures below 230 K, exhibiting a peak to valley ratio of 3:1 at 4.2 K.
Źródło:
Acta Physica Polonica A; 1995, 88, 5; 885-888
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Universal Behaviour of Magnetoconductance due to Weak Localization in Two-Dimensional Systems - Example of GaInAs Quantum Wells
Autorzy:
Zduniak, A.
Dyakonov, M. I.
Litwin-Staszewska, E.
Knap, W.
Powiązania:
https://bibliotekanauki.pl/articles/1943851.pdf
Data publikacji:
1995-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.61.Ey
73.20.Dx
Opis:
Weak localization corrections to conductivity of a two-dimensional electron gas are studied by measurements of the magnetic field dependence of the conductivity in GalnAs quantum wells. We observe that, when presented as a function of the normalized magnetic field (x = B/B$\text{}_{tr}$, where B is the magnetic field, B$\text{}_{tr}$ = ħ/4eτD, D is the diffusion constant and τ is momentum relaxation time), different samples show very similar high field behaviour. A theoretical description is developed that allows one to describe in a consistent way high and low field behaviour. The theory predicts universal (B$\text{}^{1}\text{}^{/}\text{}^{2}$) behaviour of the conductivity correction for all 2D systems in the high field limit (r > 1). Low field behaviour depends strongly on spin and phase relaxation mechanisms. Comparison of the theory with experiment confirms the universal behaviour in the high field limit and allows one to estimate the spin and phase relaxation times for different GaInAs quantum wells.
Źródło:
Acta Physica Polonica A; 1995, 88, 5; 1053-1057
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Screening and Electric Field on Exciton Binding Energy in Asymmetric Double Quantum Well
Autorzy:
Olejníková, B.
Powiązania:
https://bibliotekanauki.pl/articles/1872757.pdf
Data publikacji:
1995-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.40.Kp
73.20.Dx
Opis:
The influence of screening by confined free electrons on the exciton binding energy in the asymmetric double quantum well is calculated for various values of applied electric field perpendicular to the layer plane. The dependence of the exciton binding energy on carrier concentration is found to be stronger for lower than for higher fields. The drop of field-dependent exciton energy is less remarkable at higher densities of free electrons. Calculations were performed at 10 and 300 K, and up to densities of 10$\text{}_{14}$ m$\text{}^{-2}$ and 7 × 10$\text{}^{14}$ m$\text{}^{-2}$, respectively.
Źródło:
Acta Physica Polonica A; 1995, 87, 2; 353-356
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Tunnelling of Direct and Indirect Excitons in Slightly Asymmetric Double Quantum Wells
Autorzy:
Mazurenko, D. A.
Akimov, A. V.
Moskalenko, E. S.
Zhmodikov, A. L.
Kaplyanskii, A. A.
Challis, L. J.
Cheng, T. S.
Foxon, C. T.
Powiązania:
https://bibliotekanauki.pl/articles/1952066.pdf
Data publikacji:
1996-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
63.20.Kr
Opis:
We report the first studies of luminescence spectra from asymmetric double quantum wells of GaAs with widths around 100 Å differing by only one (2.8 Å) or two monolayers. Studies of the position and intensity of the direct and indirect exciton lines suggest the existence of acoustic phonon-assisted tunnelling between exciton states separated by a few meV. At temperatures 10-20 K the electron tunnelling process is fast enough to maintain thermal equilibrium between these direct and indirect excitons which are connected with holes in the same quantum well.
Źródło:
Acta Physica Polonica A; 1996, 90, 5; 895-898
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Variational Calculation for Triangular Quantum Wells Using Modified Trial Wave Function
Autorzy:
Pödör, B.
Powiązania:
https://bibliotekanauki.pl/articles/1933949.pdf
Data publikacji:
1995-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
72.20.Dp
73.20.Dx
Opis:
In calculations involving triangular quantum wells the Fang-Howard variational wave function is widely used because of its simplicity, although it can lead to substantial errors. This can also occur in transport calculations, where the scattering rate, being proportional to the integral of the fourth power of the wave function, depends strongly on the shape of the wave function. A new set of one-parameter wave functions is introduced and the relaxation time is evaluated for short range scatterers. The improved wave function leads up to about 22 per cent increase in the scattering rate, and to a comparable decrease in the relaxation time.
Źródło:
Acta Physica Polonica A; 1995, 88, 5; 869-872
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Resonant Conductance of Two-Dimensional Electron Systems
Autorzy:
Matulis, A.
Patiejūnas, K.
Powiązania:
https://bibliotekanauki.pl/articles/1921614.pdf
Data publikacji:
1992-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
72.20.Dp
Opis:
The ballistic conductance of two-dimensional ring calculation results are presented. The influence of the magnetic field and electron elastic scattering on the resonant ring conductance are discussed.
Źródło:
Acta Physica Polonica A; 1992, 82, 4; 709-712
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electron Damping in Surface Studies
Autorzy:
Bartoš, I.
Powiązania:
https://bibliotekanauki.pl/articles/1892162.pdf
Data publikacji:
1992-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.20.-b
73.20.Dx
Opis:
Electron correlation is responsible for finite lifetimes of excited electrons in crystals. Lifetime energy dependence can be obtained for infinite jellium model and only very recently the first results for an infinite crystal have been evaluated (GW approximation). Here, a phenomenological approach, based on Green functions, is presented. Broadening of local densities of electron states as well as that of angular-resolved photoemission (ARUPS) peaks and very-low-energy-electron diffraction (VLEED) profiles, due to the imaginary component of the optical potential is reviewed and interpreted. Anisotropy of electron damping on crystal surfaces has been found in VLEED as a result of electron channeling along the densely packed (111) surface atomic planes in fcc crystals. Interpretation of peak widths in VLEED-and ARUPS-profiles provides a mean to learn about damping of electrons, excited on crystal surface.
Źródło:
Acta Physica Polonica A; 1992, 81, 1; 33-37
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
(120)-Oriented CdTe/CdMnTe Quantum Well Structures Grown by Molecular Beam Epitaxy
Autorzy:
Kutrowski, M.
Karczewski, G.
Cywiński, G.
Surma, M.
Grasza, K.
Łusakowska, E.
Kossut, J.
Wojtowicz, T.
Powiązania:
https://bibliotekanauki.pl/articles/1952037.pdf
Data publikacji:
1996-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
78.55.Et
Opis:
We report on the MBE growth and magnetooptical studies of (120)-oriented CdTe/CdMnTe quantum well structures. The quality of structures, as evaluated by the photoluminescence line width, was as good as that of the best structures grown in ⟨100⟩ direction. No spin splitting enhancement, expected theoretically, due to the reduction of the antiferromagnetic interaction between Mn ions in CdTe/CdMnTe digital alloy quantum wells grown along ⟨120⟩ direction was observed.
Źródło:
Acta Physica Polonica A; 1996, 90, 5; 879-882
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Field Dependent Coupling of Valence Band States in Asymmetric Double Quantum Wells
Autorzy:
Suisky, D.
Neugebauer, F.
Enders, P.
Powiązania:
https://bibliotekanauki.pl/articles/1952713.pdf
Data publikacji:
1996-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
78.66.-w
Opis:
We discuss a theoretical model for the Zeeman splitting in dimension reduced structures consisting of semimagnetic semiconducting materials. The interplay of the magnetic field in different orientations with the confinement and strain induced symmetry reduction in quantum well structures is discussed. The coupling of valence band states of magnetic and nonmagnetic wells in asymmetric double quantum well structures is studied.
Źródło:
Acta Physica Polonica A; 1996, 90, 5; 1095-1099
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Characterization of Effective Masses and Optical Gain in Strained Quantum-Well Lasers
Autorzy:
Wartak, M. S.
Ma, T.-M.
Li, Z.-M.
Makino, T.
Powiązania:
https://bibliotekanauki.pl/articles/1934047.pdf
Data publikacji:
1995-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.25.Jd
73.20.Dx
Opis:
Valence-band structures, hole effective masses and optical gain have been calculated for strained-layer quantum-well laser structures. Results show a logarithmic relation between the peak optical gain and carrier concentration for all possible material compositions of the quaternary system.
Źródło:
Acta Physica Polonica A; 1995, 88, 5; 949-952
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dependence of Exciton Binding Energy on Magnetic Field in Parabolic Quantum Well Made of Diluted Magnetic Semiconductors
Autorzy:
Kyrychenko, F.
Kossut, J.
Powiązania:
https://bibliotekanauki.pl/articles/1991631.pdf
Data publikacji:
1998-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.35.Cc
73.20.Dx
Opis:
Influence of an external magnetic field on exciton binding in parabolic quantum wells composed of diluted magnetic semiconductors are studied variationally using separable trial wave functions. The effect is due to a change of shape of the confining potential induced by an external magnetic field. The validity of the results of the calculations is checked by solving numerically the corresponding one-dimensional Schrodinger equations. Further, we check the results by performing variational calculations in the case of the Ex11 exciton (i.e. with electron and hole in their ground subbands) with a non-separable trial wave function. It is shown that, contrary to the case of a rectangular quantum well, for the parabolic quantum well the magnetic field dependence of the binding energy is significant.
Źródło:
Acta Physica Polonica A; 1998, 94, 3; 406-410
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Weakly Diluted Magnetic CdTe/Cd$\text{}_{1-x}$Mn$\text{}_{x}$Te Semiconductor Structures Grown by MBE
Autorzy:
Wojtowicz, Τ.
Karczewski, G.
Kossut, J.
Powiązania:
https://bibliotekanauki.pl/articles/1933693.pdf
Data publikacji:
1995-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
78.55.Et
Opis:
In this paper we review the results of our effort to grow layers and low-dimensional structures containing Cd$\text{}_{1-x}$Μn$\text{}_{x}$Te diluted magnetic semiconductor with relatively high values of Mn molar fraction x. A high quality of the structures grown so far is demonstrated by making use of results of several selected experiments. In the case of the epilayers having bulk-like thickness with x ≥ 0.7 we discuss, in particular, the magnetic phase diagram as well as we report on collective spin excitation (magnons) observed in Raman scattering experiments. The discussion of the growth of different quantum wells, including rectangular, digital, parabolic and wedge quantum wells, is accompanied by a brief overview of their optical and magnetooptical properties. These results include first measurements concerning magnetic polarons in quantum wells embedded in Cd$\text{}_{1-x}$Mn$\text{}_{x}$Te barriers with 0.4 ≤ x ≤ 0.8. Finally, we report on the present status of the search for dimensional effects in the spin-glass phase performed with the use of our specially designed superlattice structures.
Źródło:
Acta Physica Polonica A; 1995, 88, 4; 631-642
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
ZnS/ZnSe Superlattices under Pressure
Autorzy:
Gorczyca, I.
Christensen, N. E.
Powiązania:
https://bibliotekanauki.pl/articles/1929746.pdf
Data publikacji:
1993-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.25.Tn
73.20.Dx
Opis:
Self-consistent linear muffin-tin orbital method is used to calculate the band structure of ZnS/ZnSe (001) strained-layer superlattice and investigate the influence of hydrostatic pressure on the valence band offset (VBO). Three different strain modes corresponding to various values of the relative thicknesses of both materials are considered. A I → II type conversion associated with the conduction-band crossover between the ZnSe well and ZnS barrier layers is found in agreement with recent experimental data.
Źródło:
Acta Physica Polonica A; 1993, 84, 4; 753-756
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New Method for Studying Biaxial Deformation Effects on Optical Spectra of Quantum Wells
Autorzy:
Sosin, T. P.
Trzeciakowski, W.
Powiązania:
https://bibliotekanauki.pl/articles/1931925.pdf
Data publikacji:
1995-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.66.Fd
73.20.Dx
Opis:
The effects of large deformation were studied by preparing thin (20-30 μm) membranes with quantum-well layers on top. A small gas pressure of a few bar deforms the membrane substantially and changes the optical spectra of the quantum wells. We present the results of the photoluminescence and absorption from GaAs/AlGaAs and from InGaAs/GaAs quantum wells subjected to tensile and to compressive biaxial strain. The light-hole lines shift more than two times faster than the heavy-hole lines so that they cross under tensile strain.
Źródło:
Acta Physica Polonica A; 1995, 87, 1; 151-156
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Digital Magnetic Quantum Wells for the Study of Interface Sharpness of Molecular Beam Epitaxy Grown Structures
Autorzy:
Wojtowicz, T.
Karczewski, G.
Żakrzewski, A.
Kutrowski, M.
Janik, E.
Dynowska, E.
Kopalko, K.
Kret, S.
Kossut, J.
Laval, J. Y.
Powiązania:
https://bibliotekanauki.pl/articles/1931933.pdf
Data publikacji:
1995-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
78.55.Et
Opis:
We report on the growth and basic characterization of digital magnetic quantum wells, that is, quantum wells in which the well material is itself a short period superlattice composed of alternating diluted magnetic and nonmagnetic semiconductor layers each only a few monolayers thick. These novel structures can be useful in a variety of studies, including studies of barrier-well interface sharpness.
Źródło:
Acta Physica Polonica A; 1995, 87, 1; 165-168
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
New Numerical Matrix Methods of Solving the Quasi-One-Dimensional Effective-Mass Equation
Autorzy:
Salejda, W.
Tyc, M. H.
Andrzejewski, J.
Kubisa, M.
Misiewicz, J.
Just, M.
Ryczko, K.
Powiązania:
https://bibliotekanauki.pl/articles/2008323.pdf
Data publikacji:
1999-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
02.70.Bf
73.20.Dx
Opis:
New efficient numerical methods of computing eigenvalues and eigenvectors of quasi-one-dimensional effective-mass Hamiltonian with arbitrary coordinate dependence of charge carrier mass are presented. Within the proposed approach the effective-mass equation is replaced by a nonsymmetric or symmetric matrix eigenproblem which can be analysed numerically with the help of existing computer routines. The presented methods are verified in special semiconductor heterostructure cases that are solvable within other approaches. A generalization of the presented methods for nonparabolic materials is also discussed.
Źródło:
Acta Physica Polonica A; 1999, 95, 6; 881-896
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical Analysis of Optical Gain in Quantum Well Lasers Including Valence-Band Mixing Effect
Autorzy:
Łepkowski, S.
Bugajski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1968351.pdf
Data publikacji:
1997-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
42.55.Px
Opis:
The linear optical gain in the AlGaAs/GaAs quantum well lasers is studied theoretically, taking into account the valence-band mixing effect. Our approach is based on the multiband effective-mass theory (k p method) and the density-matrix formalism. In order to obtain the valence bands' structure we employ the 4×4 Luttinger-Kohn Hamiltonian, neglecting the coupling to the split-off band. The spectral dependence of the linear optical gain is calculated using the density-matrix method with interband relaxation. Finally, we analyse the spatial distribution of the optical gain in the quantum well region for the photon energy corresponding to the peak value of the linear gain.
Źródło:
Acta Physica Polonica A; 1997, 92, 5; 903-907
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bound-to-Continuum Transitions in Quantum Well with Capping Barrier Layer of Finite Size
Autorzy:
Nalewajko, C.
Załużny, M.
Powiązania:
https://bibliotekanauki.pl/articles/1968359.pdf
Data publikacji:
1997-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.30.Fs
73.20.Dx
Opis:
It was shown employing the functional density approach that interference effects resulting from finite size of the cap layer can modify substantially the absorption line shape connected with bound-to-continuum intraband transitions in quantum wells.
Źródło:
Acta Physica Polonica A; 1997, 92, 5; 908-910
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fermi-Edge Singularity in Luminescence Spectra of P-Type Modulation Doped AlGaAs/GaAs Quantum Wells
Autorzy:
Bugajski, M.
Godlewski, M.
Regiński, K.
Holtz, P. O.
Bergman, J. P.
Monemar, B.
Powiązania:
https://bibliotekanauki.pl/articles/1969046.pdf
Data publikacji:
1998-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
42.55.Px
73.20.Dx
Opis:
We have studied an enhancement of the oscillator strength for optical transitions near the Fermi energy in p-type modulation-doped quantum wells, which, so far, deserved much less attention than analogous n-type systems, because of the complicated valence band structure involved. The relatively wide (L=150 Å) quantum wells and high doping levels were used, containing more than one occupied subband. The enhancement in the photoluminescence intensity at the Fermi energy resulted from the strong correlation and multiple scattering of holes near the Fermi edge by the localized electrons.
Źródło:
Acta Physica Polonica A; 1998, 94, 2; 265-270
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Wave Functions of Disordered Two-Dimensional Electron Gas in Strong Magnetic Field
Autorzy:
Wysokiński, K. I.
Brenig, W.
Powiązania:
https://bibliotekanauki.pl/articles/1891431.pdf
Data publikacji:
1991-09
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
72.10.Bg
73.20.Dx
Opis:
The wave functions of the disordered two-dimensional electron gas (2DEG) placed in strong perpendicular magnetic field are calculated numerically. Even though the purpose of this work is mainly pedagogical, we shall shortly discuss our motivation which is possible application of the results to the calculations of the conductivity tensor in transition region between consecutive plateaus of the Hall conductivity in the quantum Hall effect.
Źródło:
Acta Physica Polonica A; 1991, 80, 3; 469-473
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the Absorption of Infrared Radiation by Electrons in Step Quantum Wells
Autorzy:
Załużny, M.
Nalewajko, C.
Powiązania:
https://bibliotekanauki.pl/articles/1876100.pdf
Data publikacji:
1995-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.30.Fs
73.20.Dx
Opis:
The influence of the depolarization effect on the spectral characteristics of intraband absorption on bound-free transitions in semiconductor quantum wells is analyzed using the local and nonlocal theories. The results obtained show that the local theory only qualitatively describes the modification of the bound-free absorption spectrum by the depolarization effect.
Źródło:
Acta Physica Polonica A; 1995, 87, 2; 449-452
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Photoelectron Spectroscopy by Synchrotron Radiation
Autorzy:
Nilsson, P. O.
Powiązania:
https://bibliotekanauki.pl/articles/1920869.pdf
Data publikacji:
1992-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
79.60.-i
Opis:
The present understanding of the photoemission effect is reviewed. Simple and more advanced models are used for interpreting photoelectron spectroscopy data from valence bands and core levels in solids. A few experimental results are presented to illustrate the present status of the technique.
Źródło:
Acta Physica Polonica A; 1992, 82, 2; 201-219
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optical Processes in Quantum Wells
Autorzy:
Sham, L. J.
Powiązania:
https://bibliotekanauki.pl/articles/1931845.pdf
Data publikacji:
1995-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.20.Dx
78.55.Cr
Opis:
A review is given of the theoretical framework of exciton dynamics in quantum wells including the spin degrees of freedom. A study is made of various momentum, energy, and spin relaxation mechanisms including the effects of exciton-phonon interaction, the single-particle spin-flips by means of spin-orbit interaction and the exciton spin-flip by means of the exchange interaction. All these competing mechanisms are taken into account in a set of equations governing the time evolution of the exciton spin populations. Solutions are then used to interpret observed time-resolved observations of polarized luminescence spectra. For excitons in a two-dimensional system such as a semiconductor quantum well, the breaking of the translational symmetry in the direction normal to the interface plane has been shown theoretically by Hanamura, by Andreani and Bassani, and by Citrin to result in a recombination rate much faster than in a three-dimensional system. Yet, experiments show comparable decay rates in two- and three-dimensional excitons. Recent experiments with high time resolutions show two decay times for the total luminescence intensity. The slower one agrees with the one usually observed and interpreted as the radiative recombination time. We shall give an explanation for the fast decay as a combination of radiative recombination and single-particle spin-flip and for the slow decay as the radiative recombination slowed down by the presence of lower energy dark states for excitons with parallel spins. The ability to use the same theory to account for the polarization behavior confirms the importance of the exciton spin dynamics. Furthermore, the longitudinal electric field dependence is used to check our theory of exchange.
Źródło:
Acta Physica Polonica A; 1995, 87, 1; 7-15
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Multiple-Band Envelope-Function Approximation for the Magnetooptical Anisotropy of Excitons in Strained Semimagnetic Semiconductors
Autorzy:
Suisky, D.
Neugebauer, F.
Röseler, J.
Rex, S.
Powiązania:
https://bibliotekanauki.pl/articles/1923930.pdf
Data publikacji:
1992-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.70.Ak
73.20.Dx
Opis:
The magnetooptical anisotropy in strained quantum well structures is studied theoretically. As the source of this anisotropy the magnetic field induced mixing of light and heavy hole states is found. The anisotropy is also found in the frame of the multiple-band envelope-function approximation studying the influence of the barrier material on electronic states in the quantum well.
Źródło:
Acta Physica Polonica A; 1992, 82, 5; 861-864
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