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1.
S. V. Gupalov E. L. Ivchenko A. V. Kavokin 《Journal of Experimental and Theoretical Physics》1998,86(2):388-394
A theory is constructed for the long-range exchange and retarding interactions between an electron and a hole in a quantum
well. A method is developed that makes it possible to calculate the ground and excited states of an exciton localized as a
whole on a width fluctuation of a quantum well in the form of a rectangular island. It is shown that taking into account the
electron-hole interaction mechanisms considered here causes the radiation doublet of the exciton to split into two components
polarized along the sides of the rectangle. The dependence of the magnitude and sign of this splitting on the linear dimensions
of the island and the level number of the localized exciton are analyzed.
Zh. éksp. Teor. Fiz. 113, 703–714 (February 1998) 相似文献
2.
Electron transmission in the two-, three-, and four-terminal nanostructures is considered under the influence of a radiation
field. The frequency of the radiation field is tuned to the transition between the energy of a bound state and the Fermi energy
of the incident electrons. The radiation induced resonant peaks and dips of the electron transport are exhibited for zero
and low magnetic fields. It is shown that rotation of the radiation field polarization can effectively control the electron
transport into different electrodes attached to the structures because of the symmetry of the structures. The resonant anomalies
of the Hall resistance are found in a weak magnetic field.
Zh. éksp. Teor. Fiz. 114, 1954–1970 (December 1998)
Published in English in the original Russian journal. Reproduced here with stylistic changes by the Translation Editor. 相似文献
3.
L. E. Vorob’ev 《JETP Letters》1998,68(5):417-425
A mechanism is proposed for obtaining intraband population inversion of electrons in size-quantization levels through the
injection of electron-hole pairs into the i region of a heterostructure with quantum wells or quantum dots. Key elements of the mechanism are the simultaneous generation
of interband (hv≈E
g
) near-IR radiation and the presence of a “metastable” level. In quantum wells such a level can be produced by making use
of the weak overlap of the wave functions of electrons in the levels of a quantum well of complicated configuration and exploiting
the characteristic features of the interaction of electrons with optical phonons in polar semiconductors. In quantum dots
such a level forms as a result of the phonon bottleneck effect. Estimates are made of the gain for mid-IR radiation in intraband
optical transitions of electrons.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 5, 392–399 (10 September 1998) 相似文献
4.
L. I. Korovin I. G. Lang S. T. Pavlov 《Journal of Experimental and Theoretical Physics》1997,84(6):1197-1208
The spatial correlation of light-generated electrons and holes in a quasi-two-dimensional electron gas in a strong magnetic
field is investigated in an approximation linear in the intensity of the exciting light. The correlation is due to the interaction
of the electrons and holes with longitudinal optical (LO) phonons. The theory permits calculating, on the basis of a special diagrammatic technique, two distribution functions of
an electron-hole pair with respect to the distance between the electron and the hole after the emission of N phonons: first, the function determining the total number of pairs which have emitted N phonons and, second, the function related to the rank-4 light-scattering tensor in interband resonance Raman scattering of
light. A special feature of the system is that the electron and hole energy levels are discrete. The calculation is performed
for a square quantum well with infinitely high barriers. The distribution function and the total number of electron-hole pairs
before the emission of phonons as well as the distribution function corresponding to two-phonon resonance Raman scattering
are calculated. The theory predicts the appearance of several close-lying peaks in the excitation spectrum under resonance
conditions. The number of peaks is related to the number of the Landau level participating in the optical transition. The
distance between peaks is determined by the electron-phonon coupling constant. Far from resonance there is one peak, which
is much weaker than the peaks obtained under resonance conditions.
Zh. éksp. Teor. Fiz. 111, 2194–2214 (June 1997) 相似文献
5.
The ion current of adsorbed water molecules is studied experimentally as a function of the frequency of near-IR radiation
incident on a surface at frequencies in the intrinsic vibrational bands of the water molecule. The ions are produced by nonequilibrium
field surface ionization. The observed band (near one of the combination frequencies) has a width of 100 cm−1 and is shifted relative to the free molecular band by 130 cm−1. Estimates show that the cross section for absorption of the radiation by the adsorbed molecules is 3–4 orders of magnitude
larger than for free molecules, as is typical of surface processes.
Zh. Tekh. Fiz. 69, 123–127 (September 1999) 相似文献
6.
Results are presented of investigations of the photoelectric properties of nitrided layer/GaAs (GaP) heterojunctions prepared
by plasma treatment of GaAs and GaP crystals in the presence of nitrogen ions. The heterojunctions exhibited broad-band photosensitivity
relative to the intensity of the natural radiation. It was established that when linearly polarized radiation is obliquely
incident on the surface of nitrided layers, polarization photosensitivity occurs which is controlled by the angle of incidence
Θ and increases proportionately as Θ2. The spectral dependences of the induced photopleochroism are attributed to the antireflecting properties of the wide-gap
layers. Nitrided-layer heterojunctions can be used as broad-band photoanalyzers for linearly polarized radiation.
Zh. Tekh. Fiz. 69, 138–142 (June 1999) 相似文献
7.
J. Zhu S. L. Ban S. H. Ha 《The European Physical Journal B - Condensed Matter and Complex Systems》2012,85(2):67
The binding energy of an exciton screened by the electron-hole plasma in a wurtzite
GaN/In
x
Ga1−x
N quantum well (in
the case of 0.1 < x < 1 within which the interface phonon
modes play a dominant role) is calculated including the exciton-phonon interaction by a
variational method combined with a self-consistent procedure. The coupling between the
exciton and various longitudinal-like optical phonon modes is considered to demonstrate
the polaronic effect which strongly depends on the exciton wave function. All of the
built-in electric field, the exciton-phonon interaction and the electron-hole plasma
weaken the Coulomb coupling between an electron and a hole to reduce the binding energy
since the former separates the wave functions of the electron and hole in the
z direction and the later two enlarge the exciton Bohr radius. The
electron-hole plasma not only restrains the built-in electric field, but also reduces the
polaronic effect to the binding energy. 相似文献
8.
G. M. Filippov 《Journal of Experimental and Theoretical Physics》1998,86(3):459-471
This paper examines the effect of multiple photon emission on the quantum mechanical state of an electron emitting synchrotron
radiation and on the intensity of that radiation. Calculations are done with a variant of perturbation theory based on the
use of extended coherent states. A general formula is derived for the number of emitted photons, which allows taking into
account their mutual interaction. A model problem is used to demonstrate the absence of the infrared catastrophe in the modified
perturbation theory. Finally, the electron density matrix is calculated, and the analysis of this matrix makes it possible
to conclude that the degree of the electron’s spatial localization increases with the passage of time if the electron is being
accelerated.
Zh. éksp. Teor. Fiz. 113, 841–864 (March 1998) 相似文献
9.
V. B. Timofeev A. V. Larionov P. S. Dorozhkin M. Bayer A. Forchel J. Straka 《JETP Letters》1997,65(11):877-882
When a voltage is applied to double quantum wells based on AlGaAs/GaAs heterostructures with contact regions (n-i-n structures), a two-dimensional (2D) electron gas appears in one of the quantum wells. Under illumination which generates
electron-hole pairs, the photoexcited holes become localized in a neighboring quantum well and recombine radiatively with
the 2D electrons (tunneling recombination through the barrier). The appearance, ground-state energy, and density of the degenerate
2D electron gas are determined from the structure of the Landau levels in the luminescence and luminescence excitation spectra
as well as from the oscillations of the radiative recombination intensity in a magnetic field with detection directly at the
Fermi level. The electron density is regulated by the voltage between the contact regions and increases with the slope of
the bands. For a fixed slope of the bands the 2D-electron density has an upper limit determined by the resonance tunneling
of electrons into a neighboring quantum well and subsequent direct recombination with photoexcited holes.
Pis’ma Zh. éksp. Teor. Fiz. 65, No. 11, 840–845 (10 June 1997) 相似文献
10.
J.C. Cao X.L. Lei 《The European Physical Journal B - Condensed Matter and Complex Systems》2002,29(4):553-559
We have extended the balance equations to account for conduction-valence interband impact ionization (II) process induced
by an intense terahertz (THz) electromagnetic irradiation in semiconductors, and applied them to study the II effect on electron
transport and electron-hole pair generation-recombination rate in THz-driven InAs/AlSb heterojunctions (HJ). As many as needed
multiphoton channels are self-consistently taken into account for yielding a given accuracy. The time evolution of transport
state including THz-radiation-induced II process are monitored in details by an extensive time-dependent analysis. Two different
physical stages, the quasi-steady state and the complete steady-state, are clearly identified from the present calculations.
Intersubband electron transfer rate and net electron-hole generation rate are derived as functions of the THz radiation strength
E
ac for various radiation frequencies from f
ac = 0.42 to 6 THz at lattice temperatures T = 6 K. It's indicated that the THz radiation with a larger E
ac or a lower f
ac, has a stronger effect on electron transport and II process. Qualitative agreement is obtained between the calculated electron-hole
generation rate and the available experimental data for InAs/AlSb HJ's at T = 6 K.
Received 24 May 2002 / Received in final form 26 August 2002 Published online 31 October 2002
RID="a"
ID="a"e-mail: jccao8@hotmail.com 相似文献
11.
A sharp increase of the Faraday rotation with increasing incident radiation power is observed in a band near the fundamental
absorption edge of the ferromagnetic semiconductor CdCr2 Se4. The magnitude of the effect is a nonmonotonic function of the radiation intensity. The effect is explained by narrowing
of an excitonic resonance as a result of screening of the internal electric fields by photoexcited carriers.
Pis’ma Zh. éksp. Teor. Fiz. 66, No. 6, 409–413 (25 September 1997) 相似文献
12.
A. V. Kostrov M. V. Starodubtsev C. Krafft G. Matthieussent A. S. Volokitin 《JETP Letters》1998,67(6):400-404
Experimental results concerning the interaction of a modulated electron beam with a magnetoactive plasma in the whistler frequency
range are reported. It was shown experimentally that when a beam is injected into the plasma, waves can be generated by two
possible mechanisms: Cherenkov emission of whistlers by the modulated beam, and transition radiation from the beam injection
point. In the case of weak beam currents (N
b/N
0)≪−4) the Cherenkov resonance radiation is more than an order of magnitude stronger than the transition radiation; the Cherenkov
emission efficiency decreases at high beam currents. The transformation of the distribution function of the beam is investigated
for the case of weak beam currents. It is shown that in the case of the Cherenkov interaction with whistlers the beam is retarded
and the beam distribution function becomes wider and acquires a plateau region.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 6, 378–382 (25 March 1998) 相似文献
13.
V. P. Kochereshko E. L. Ivchenko D. R. Yakovlev F. Lavallard 《Physics of the Solid State》1998,40(12):2024-2030
Exciton states in short-period GaAs/AlGaAs superlattices have been studied by optical orientation and optical dipole-moment
alignment methods. The effect of magnetic field in the Faraday and Voigt geometries on the degree of linear and circular polarization
of photoluminescence have been studied under resonant and nonresonant excitation. The constants of electron-hole exchange
interaction in the exciton have been determined.
Fiz. Tverd. Tela (St. Petersburg) 40, 2229–2235 (December 1998) 相似文献
14.
A contact-free method of modulation spectroscopy of semiconductor heterostructures is developed. The method employs the effect
of an intensity-modulated rf or microwave field on the reflection of the probe light and makes it possible to investigate
electron-hole interaction effects in different layers of a heterostructure. A model is proposed which explains the characteristic
features of the rf-modulated optical reflection spectra observed on selectively doped GaAs/AlGaAs heterostructures is proposed.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 3, 217–221 (10 February 1998) 相似文献
15.
The possibility of observing pure nuclear resonant scattering of synchrotron radiation by a multilayer structure containing
the 169Tm isotope is analyzed theoretically. The main problem is the need to suppress the enormous background of radiation scattered
by electrons. Two methods for the destructive interference of a synchrotron radiation beam in reflection at grazing incidence
by a layered system containing Tm nuclei in one of the layers are considered, and their efficiency as applied to the conditions
of third-generation synchrotron radiation sources, such as in the European Synchrotron Radiation Facility (ESRF), is calculated.
An electron scattering suppression efficiency parameter is formulated as the ratio of the integrated nuclear scattering intensity
(with a time delay) to the total prompt electron scattering intensity in assigned ranges of angles and energies. In the first
method thin films of a special type on a substrate, viz., GIAR films, are used. In the second method a new effect, which is
termed the Bragg antipeak effect and involves the destructive interference of a wave that is Bragg-diffracted in a multilayer
superlattice and a wave reflected on the upper boundary of the sample, is employed. The physical properties of the Bragg antipeak
effect are considered, and it is found that its efficiency is sufficient for practical use.
Zh. éksp. Teor. Fiz. 114, 3–22 (July 1998) 相似文献
16.
The influence of photoexcited carriers on the dynamics of the absorption spectra of GaAs/AlxGa1−2x
As multilayer quantum wells is investigated experimentally. It is found that at quasiparticle densities all the way up to
1011 cm−2 the saturation of the excitonic absorption is due to both a decrease of oscillator strength and broadening of the excitonic
lines. It is shown that in the case of femtosecond resonance laser exci-tation the decrease of oscillator strength is due
to free electron-hole pairs, while the broadening and energy shift of the excitonic lines are due to the exciton-exciton interaction.
The lifetimes of free electron-hole pairs and excitons (≈65 ps and ≈410 ps, respectively) are determined from the exponential
decrease of the change in the oscillator strength and in the width and energy position of the excitonic lines.
Pis’ma Zh. éksp. Teor. Fiz. 66, No. 3, 139–144 (10 August 1997) 相似文献
17.
S. L. Ginzburg V. F. D’yachenko V. V. Paleichik K. V. Khodataev 《Technical Physics》1999,44(2):212-217
A three-dimensional computer model, described by a system of Maxwell-Vlasov equations, for the interaction of a plasma with
the electromagnetic field was used to calculate the excitation of a field by a relativistic electron beam with a virtual cathode
oscillating in a resonance chamber. The characteristics of the generator radiation are investigated.
Zh. Tekh. Fiz. 69, 87–92 (February 1999) 相似文献
18.
It is shown that bulk semiconductors exhibit strongly asymmetric Fano-type resonance profiles in magnetoabsorption processes
involving the formation of hot electron-hole pairs (EHPs) and accompanied by the scattering of the EHPs by defects. This result
is valid for transitions to electronic states with large Landau quantum numbers, when the Coulomb interaction plays a small
role. The physical reason for such a sharp change in the magnetoabsorption coefficient as compared with the expected result
for the ordinary density of states in a quantizing magnetic field is that the electronic excitations are quasi-one-dimensional.
The form of the resonance absorption is in good qualitative agreement with the experimental data.
Pis’ma Zh. éksp. Teor. Fiz. 63, No. 8, 619–622 (25 April 1996) 相似文献
19.
M. B. Agranat S. I. Ashitkov A. V. Kirillin A. V. Kostanovskii V. E. Fortov S. I. Anisimov P. S. Kondratenko 《JETP Letters》1997,66(10):699-703
Observations of microcrystalline graphite subjected to picosecond laser pulses reveal the formation of a liquid phase with
a subsequent transition to a uniform amorphous state of a surface layer upon solidification. This phenomenon is observed on
a definite type of graphite and with the radiation incident on a plane parallel to the sixfold symmetry axis, and only for
certain parameters of the laser pulse. A structural analysis of the amorphous phase is performed by electron microscopy and
Raman scattering spectroscopy. A periodic structure with a period of the order of the wavelength of the heating pulse is formed
in the heating region. The “rulings” of this periodic structure are oriented in the direction of polarization of the heating
pulse. A study of the reflection kinetics of the probe laser pulse showed that the characteristic existence time of the liquid
phase and of the solidification process is ∼10−10 s.
Pis’ma Zh. éksp. Teor. Fiz. 66, No. 10, 661–665 (25 November 1997) 相似文献
20.
The effect of photoexcited free carriers on the absorption spectra dynamics of GaAs/AlxGa1−x
As superlattices is investigated experimentally by the pump-probe method. A sharp change in the shift of the excitonic resonance
energy from the low-to the high-energy direction is found to occur at the moment that the electromagnetic radiation of the
pump and probe beams overlap in the case of band-band excitation. This phenomenon is explained in a model of scattering of
high-energy electron-hole pairs. The dephasing time of free high-energy particles is experimentally estimated to be several
tens of femtoseconds.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 1, 62–67 (10 January 1998) 相似文献