
Oleg RaichevNational Academy of Sciences of Ukraine | ISP · Department of Theoretical Physics
Oleg Raichev
Doctor of Science
About
141
Publications
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Introduction
Skills and Expertise
Additional affiliations
August 1987 - present
Institute of Semiconductor Physics, Kyiv
Position
- Researcher
Description
- Kinetic theory of low- dimensional electron systems. Quantum magnetotransport, topological insulators, and so on.
Publications
Publications (141)
We report on the optical realization of the magneto-intersubband oscillations that have been measured in the sub-terahertz transmittance of a GaAs quantum well with two subbands occupied. Following their dc analogue, the oscillations are periodic in the inverse magnetic field with the period governed by the subband gap. Their magnitude and polariza...
By solving the classical kinetic equation near the boundary, it is studied how the boundary conditions for two-dimensional (2D) electron gas in the hydrodynamic transport regime are modified in the presence of a magnetic field B perpendicular to the 2D layer. The results are compared to the predictions of an approximate theory that describes the bo...
It is shown that the ideal boundary between a perfectly conducting electrode and electron liquid state acts as a contact whose conductance per unit area is higher than the fundamental Sharvin conductance by a numerical coefficient 2α, where α is slightly smaller than unity and depends on the dimensionality of the system. If the boundary has a finit...
An approximate analytical solution of the boundary slip problem in magnetic field is obtained by using the general form of boundary conditions for the distribution function of fermions with the isotropic energy spectrum. Exact numerical calculations of the slip length for different models of angle-dependent specularity parameter and application of...
It is shown that the ideal boundary between a perfectly conducting electrode and electron liquid state acts as a contact whose conductance per unit area is higher than the fundamental Sharvin conductance by a numerical coefficient $2 \alpha$, where $\alpha$ is slightly smaller than unity and depends on the dimensionality of the system. If the bound...
An approximate analytical solution of the boundary slip problem in magnetic field is obtained by using the general form of boundary conditions for the distribution function of fermions with the isotropic energy spectrum. Exact numerical calculations of the slip length for different models of angle-dependent specularity parameter and application of...
The double quantum well systems consisting of two HgTe layers separated by a tunnel-transparent barrier are expected to manifest a variety of phase states including two-dimensional gapless semimetal and two-dimensional topological insulator. The presence of several subbands in such systems leads to a rich filling factor diagram in the quantum Hall...
The double quantum well systems consisting of two HgTe layers separated by a tunnel-transparent barrier are expected to manifest a variety of phase states including two-dimensional gapless semimetal and two-dimensional topological insulator. The presence of several subbands in such systems leads to a rich filling factor diagram in the quantum Hall...
The interaction of electrons with a flux of ballistic phonons leads to excitation of many angular harmonics of an electron distribution function. We show that this property dramatically modifies the magnetothermoelectric phenomena in two-dimensional electron systems with boundaries. By considering classical magnetotransport of electrons in a narrow...
The two-dimensional topological insulator phase has been observed previously in single HgTe-based quantum wells with inverted subband ordering. In double quantum wells (DQWs), coupling between the layers introduces additional degrees of freedom leading to a rich phase picture. By studying local and nonlocal resistance in HgTe-based DQWs, we observe...
We develop a classical kinetic theory of magnetotransport of 2D electrons in narrow channels with partly diffusive boundary scattering and apply it to description of magnetoresistance measured in the temperature interval 4.2-30 K in long mesoscopic bars fabricated from high-purity GaAs quantum well structures. Both experiment and theory demonstrate...
The linear response of two-dimensional electron gas in a perpendicular magnetic field in the presence of a spatially dependent classically smooth electrostatic potential is studied theoretically, by application of the Kubo formula for nonlocal conductivity tensor. In the classical transport regime, a general expression for the conductivity tensor t...
It is shown that the classical commensurability phenomena in weakly modulated two-dimensional electron systems is a manifestation of the intrinsic properties of the correlation functions describing a homogeneous electron gas in a magnetic field. The theory demonstrates the importance for consideration of nonlocal response and removes the gap betwee...
We develop a classical kinetic theory of magnetotransport of 2D electrons in narrow channels with partly diffusive boundary scattering and apply it to the description of magnetoresistance measured in the temperature interval 4.2–30 K in long mesoscopic bars fabricated from high-purity GaAs quantum well structures. Both experiment and theory demonst...
We develop a theory of nonlinear response to an electric field of two-dimensional (2D) fermions with topologically nontrivial wave functions characterized by the Berry phase Φn=nπ,n=1,2,.... In particular, we find that owing to the suppression of backscattering at odd n, Hall field-induced resistance oscillations, which stem from elastic electron t...
The two-dimensional topological insulator phase has been observed previously in single HgTe-based quantum wells with inverted subband ordering. In double quantum wells (DQWs), coupling between the layers introduces additional degrees of freedom leading to a rich phase picture. By studying local and nonlocal resistance in HgTe-based DQWs, we observe...
We develop a theory of nonlinear response to an electric field of two-dimensional (2D) fermions with topologically non-trivial wave functions characterized by the Berry phase $\Phi_n = n \pi, n = 1,2,...$. In particular, we find that owing to suppression of backscattering at odd $n$, Hall field-induced resistance oscillations, which stem from elast...
We have measured the differential resistance in a two-dimensional topological insulator (2DTI) in a HgTe quantum well, as a function of the applied dc current. The transport near the charge neutrality point is characterized by a pair of counter propagating gapless edge modes. In the presence of an electric field, the energy is transported by counte...
We have measured the differential resistance in a two-dimensional topological insulator (2DTI) in a HgTe quantum well, as a function of the applied dc current. The transport near the charge neutrality point is characterized by a pair of counter propagating gapless edge modes. In the presence of an electric field, the energy is transported by counte...
The thermoelectric response of HgTe quantum wells in the state of two-dimensional topological insulator (2D TI) has been studied experimentally. Ambipolar thermopower, typical for an electron-hole system, has been observed across the charge neutrality point, where the carrier type changes from electrons to holes according to the resistance measurem...
The thermoelectric response of HgTe quantum wells in the state of two-dimensional topological insulator (2D TI) has been studied experimentally. Ambipolar thermopower, typical for an electron-hole system, has been observed across the charge neutrality point, where the carrier type changes from electrons to holes according to the resistance measurem...
The linear response of a two-dimensional electron gas in a perpendicular magnetic field in the presence of a spatially dependent classically smooth electrostatic potential is studied theoretically, by application of the Kubo formula for a nonlocal conductivity tensor. In the classical transport regime, a general expression for the conductivity tens...
It is shown that the classical commensurability phenomena in weakly modulated two-dimensional electron systems is a manifestation of the intrinsic properties of the correlation functions describing a homogeneous electron gas in a magnetic field. The theory demonstrates the importance for consideration of nonlocal response and removes the gap betwee...
We report on nonlinear transport measurements in a two-dimensional electron gas hosted in GaAs/AlGaAs heterostructures. Upon application of direct current, the low-temperature differential resistivity acquires a positive correction, which exhibits a pronounced maximum followed by a plateau. With increasing temperature, the nonlinearity diminishes a...
We report on nonlinear transport measurements in a two-dimensional electron gas hosted in GaAs/AlGaAs heterostructures. Upon application of direct current, the low-temperature differential resistivity acquires a positive correction, which exhibits a pronounced maximum followed by a plateau. With increasing temperature, the nonlinearity diminishes a...
By measuring the thermoelectric effect in high-mobility quantum wells with two occupied subbands in perpendicular magnetic field, we detect magnetophonon oscillations due to interaction of electrons with acoustic phonons. These oscillations contain specific features identified as combined resonances caused by intersubband phonon-assisted transition...
By measuring the thermoelectric effect in high-mobility quantum wells with two occupied subbands in perpendicular magnetic field, we detect magnetophonon oscillations due to interaction of electrons with acoustic phonons. These oscillations contain specific features identified as combined resonances caused by intersubband phonon-assisted transition...
The interaction of electrons with acoustic phonons under a magnetic field leads to a remarkable kind of magnetophonon oscillation of transport coefficients, recently discovered in two-dimensional electron systems. The present study shows that similar oscillations exist in bulk conductors and provides a theory of this phenomenon for the case of sphe...
To study the influence of microwave irradiation on two-dimensional electrons, we apply a method based on capacitance measurements in GaAs quantum well samples where the gate covers a central part of the layer. We find that the capacitance oscillations at high magnetic fields, caused by the oscillations of thermodynamic density of states, are not es...
To study the influence of microwave irradiation on two-dimensional electrons, we apply a method based on capacitance measurements in GaAs quantum well samples where the gate covers a central part of the layer. We find that the capacitance oscillations at high magnetic fields, caused by the oscillations of thermodynamic density of states, are not es...
We observe the phonon-drag voltage oscillations correlating with the
resistance oscillations under microwave irradiation in a two-dimensional
electron gas in perpendicular magnetic field. This phenomenon is explained by
the influence of dissipative resistivity modified by microwaves on the
phonon-drag voltage perpendicular to the phonon flux. When...
The response of two-dimensional electron gas to temperature gradient in
perpendicular magnetic field under steady-state microwave irradiation is
studied theoretically. The electric currents induced by temperature gradient
and the thermopower coefficients are calculated taking into account both
diffusive and phonon-drag mechanisms. The modification...
The magnetic field opens a gap in the edge state spectrum of two-dimensional
topological insulators thereby destroying protection of these states against
backscattering. To relate properties of this gap to parameters of the system
and to study dynamics of electrons in edge states in the presence of
inhomogeneous potentials, the effective Hamiltonia...
Our experimental studies of electron transport in wide (14 nm) HgTe quantum
wells confirm persistence of a two-dimensional topological insulator state
reported previously for narrower wells, where it was justified theoretically.
Comparison of local and nonlocal resistance measurements indicate edge state
transport in the samples of about 1 mm size...
We report transport measurements in HgTe-based quantum wells with well width of 8 nm, corresponding to the quantum spin Hall state, subject to in-plane magnetic field. In the absence of the magnetic field the local and nonlocal resistances behave very similarly, which confirms the edge state transport in our system. In the magnetic field, we observ...
The transport properties of the two-dimensional system in HgTe-based quantum
wells containing simultaneously electrons and holes of low densities are
examined. The Hall resistance, as a function of perpendicular magnetic field,
reveals an unconventional behavior, different from the classical N-shaped
dependence typical for bipolar systems with elec...
The effective 6×6 matrix Hamiltonian for two-dimensional states in HgTe/CdTe quantum wells is derived. The use of the extended basis (in contrast to the previously studied 4×4 matrix Hamiltonian) allows us to describe quantum wells with arbitrary orientation of interfaces and investigate the influence of in-plane magnetic field. The Hamiltonian is...
We experimentally demonstrate the existence of microwave-induced zero-resistance states (ZRS) in bilayer electron systems created in wide quantum wells. In contrast to single-layer two-dimensional electron systems, ZRS are developed from the strongest magneto-intersubband oscillation peaks inverted by microwave radiation. Our experimental work is d...
In this work we report on the observation of zero-resistance induced by
microwave irradiation in a bilayer electron system formed by
high-mobility wide quantum wells. The observed zero-resistance states
(ZRS) are distinct from ZRS in single layer systems and develop for
inverted magneto-intersubband oscillations. We find that the inelastic
mechanis...
We study nonlinear transport phenomena in a high-mobility bilayer system with two closely spaced populated electronic subbands in a perpendicular magnetic field. For a moderate direct current excitation, we observe zero-differential-resistance states with a characteristic 1/B periodicity. We investigate, both experimentally and theoretically, the H...
The influence of microwave irradiation on dissipative and Hall resistance in
high-quality bilayer electron systems is investigated experimentally. We
observe a deviation from odd symmetry under magnetic field reversal in the
microwave-induced Hall resistance $\Delta R_{xy}$ whereas the dissipative
resistance $\Delta R_{xx}$ obeys even symmetry. Stu...
We observe zero-differential resistance states at low temperatures and
moderate direct currents in a bilayer electron system formed by a wide quantum
well. Several regions of vanishing resistance evolve from the inverted peaks of
magneto-intersubband oscillations as the current increases. The experiment,
supported by a theoretical analysis, suggest...
Experimental studies of magnetoresistance in high-mobility wide quantum wells reveal oscillations which appear with an increase in temperature to 10 K and whose period is close to that of Shubnikov-de Haas oscillations. The observed phenomenon is identified as magnetointersubband oscillations caused by the scattering of electrons between two occupi...
The interference of magneto-intersubband oscillations and microwave-induced resistance oscillations is studied in high-density triple quantum wells. We give an introduction into magnetotransport in trilayer systems and focus on photoresistance measurements. The power and frequency dependence of the observed magnetoresistance oscillations can be des...
Magnetotransport measurements on a high-mobility electron bilayer system formed in a wide GaAs quantum well reveal vanishing dissipative resistance under continuous microwave irradiation. Profound zero-resistance states (ZRS) appear even in the presence of additional intersubband scattering of electrons. We study the dependence of photoresistance o...
Magnetotransport measurements on a high-mobility electron bilayer system formed in a wide GaAs quantum well reveal vanishing dissipative resistance under continuous microwave irradiation. Profound zero-resistance states (ZRS) appear even in the presence of additional intersubband scattering of electrons. We study the dependence of photoresistance o...
A theory of the quantum oscillations of resistivity due to interaction of two-dimensional electrons with impurities and acoustic phonons in the presence of perpendicular magnetic field is developed for multisubband systems. A comparison of the theory with recent experimental data for a quantum well with two occupied subbands demonstrates a good agr...
A microscopic theory of the phonon-induced resistance oscillations in weak perpendicular magnetic fields is presented. The calculations are based on the consideration of interaction of two-dimensional electrons with three-dimensional (bulk) acoustic phonons and take into account anisotropy of the phonon spectrum in cubic crystals. The magnetoresist...
The influence of electron-phonon interaction on magnetotransport in two-dimensional electron systems under microwave irradiation is studied theoretically. Apart from the phonon-induced resistance oscillations which exist in the absence of microwaves, the magnetoresistance of irradiated samples contains oscillating contributions due to electron scat...
We report on temperature-dependent magnetoresistance measurements in balanced double quantum wells exposed to microwave irradiation for various frequencies. We have found that the resistance oscillations are described by the microwave-induced modification of electron distribution function limited by inelastic scattering (inelastic mechanism), up to...
We report on integer and fractional microwave-induced resistance oscillations in a 2D electron system with high density and moderate mobility, and present results of measurements at high microwave intensity and temperature. Fractional microwave-induced resistance oscillations occur up to fractional denominator 8 and are quenched independently of th...
We present magnetotransport studies of high-density triple quantum well samples with different barrier widths. Because of electron transitions between three occupied 2D subbands, the magnetoresistance shows magneto-intersubband oscillations whose periodicity is determined by the subband separation energies. Temperature-dependent measurements allow...
The interference of microwave-induced resistance oscillations and magneto-intersubband oscillations in double quantum wells exposed to a continuous microwave irradiation is under study. By comparing experimental and theoretical magnetoresistance traces at different temperatures, we confirm that the inelastic mechanism of photoresistance explains ou...
Magnetoresistance of two-dimensional electron systems with several occupied subbands oscillates owing to periodic modulation of the probability of intersubband transitions by the quantizing magnetic field. In addition to previous investigations of these magneto-intersubband (MIS) oscillations in two-subband systems, we report on both experimental a...
Magnetotransport measurements in triple-layer electron systems with high carrier density reveal fractional quantum Hall effect at total filling factors ν>2. With an in-plane magnetic field we are able to control the suppression of interlayer tunneling which causes a collapse of the integer quantum Hall plateaus at ν=2 and ν=4, and an emergence of f...
We observe a large positive magnetoresistance in a bilayer electron system (double quantum well) as the latter is driven by the external gate from double to single layer configuration. Both classical and quantum contributions to magnetotransport are found to be important for explanation of this effect. We demonstrate that these contributions can be...
A microscopic theory of the phonon-induced resistance oscillations in weak perpendicular magnetic fields is presented. The calculations are based on the consideration of interaction of two-dimensional electrons with three-dimensional (bulk) acoustic phonons and take into account anisotropy of the phonon spectrum in cubic crystals. The magnetoresist...
We report on the observation of microwave-induced resistance oscillations associated with the fractional ratio n/m of the microwave irradiation frequency to the cyclotron frequency for m up to 8 in a two-dimensional electron system with high electron density. The features are quenched at high microwave frequencies independent of the fractional orde...
We report on the observation of microwave-induced resistance
oscillations associated with the fractional ratio n/m of the microwave
irradiation frequency to the cyclotron frequency for m up to 8 in a
two-dimensional electron system with high electron density. The features
are quenched at high microwave frequencies independent of the fractional
orde...
We report in detail oscillatory magnetoresistance in double quantum wells under microwave irradiation. The experimental investigation contains measurements of frequency, power and temperature dependence. In theory, the observed interference oscillations are explained in terms of the influence of subband coupling on the frequency-dependent photoindu...
The influence of magnetic fields on the electron spin in solids involves two basic mechanisms. First, any magnetic field introduces the Zeeman splitting of electron states, thereby modifying spin precession. Second, since the magnetic field affects the electron motion in the plane perpendicular to the field, the spin dynamics is also modified, owin...
We study the evolution of low-temperature magnetoresistance in double quantum
wells in the region below 1 Tesla as the applied current density increases. A
flip of the magneto-intersubband oscillation peaks, which occurs as a result of
the current-induced inversion of the quantum component of resistivity, is
observed. We also see splitting of these...
We observe oscillatory magnetoresistance in double quantum wells under microwave irradiation. The results are explained in terms of the influence of subband coupling on the frequency-dependent photoinduced part of the electron distribution function. As a consequence, the magnetoresistance demonstrates the interference of magneto-intersubband oscill...
The dynamic (ac) conductivity tensor of quantum wells with two populated subbands in the presence of a magnetic field perpendicular to the well layer is calculated theoretically. The microscopic theory is based on the Kubo formalism assuming a detailed consideration of elastic scattering of electrons by the random disorder potential with arbitrary...
We present experimental and theoretical studies of the magnetoresistance oscillations induced by resonance transitions of electrons between tunnel-coupled states in double quantum wells. The suppression of these oscillations with increasing temperature is irrelevant to the thermal broadening of the Fermi distribution and reflects the temperature de...
It is shown that the electric field applied in the plane of two-dimensional hole layers not only excites the intrinsic spin currents, but also leads to a homogeneous spin polarization. Theoretical study of this phenomenon, taking into account both the anisotropy of the Luttinger Hamiltonian and the bulk inversion asymmetry effects for holes, is car...
The spin-Hall conductivity in spatially-homogeneous two-dimensional electron systems described by the spin-orbit Hamiltonian \hbar \Omega_p \sigma is presented as a sum of the universal part Me/8 \pi \hbar determined by the Berry phase \Phi=M \pi (M is an odd integer, the winding number of the vector \Omega_p) and a non-universal part which vanishe...
Dynamic response of two-dimensional electron systems with spin-orbit interaction is studied theoretically on the basis of quantum kinetic equation, taking into account elastic scattering of electrons. The spin polarization and spin current induced by the applied electric field are calculated for the whole class of electron systems described by p-li...
Spin current of two-dimensional holes occupying the ground-state subband in an asymmetric quantum well and interacting with static disorder potential is calculated in the presence of a weak magnetic field H perpendicular to the well plane. Both spin-orbit coupling and Zeeman coupling are taken into account. It is shown that the applied electric fie...
Theoretical description of the field emission of electrons from nanoscale
objects weakly coupled to the cathode is presented. It is shown that the field-
emission current increases in a step-like fashion due to single-electron
charging which leads to abrupt changes of the effective electric field
responsible for the field emission. A detailed consi...
Transient magnetotransport of electrons with partially-inverted distribution excited by an ultrashort optical pulse is studied theoretically. The time-dependent photoconductivity is calculated for both bulk and two-dimensional semiconductor layers by taking into account the relaxation of electron distribution caused by non-elastic electron-phonon i...
Dense ensembles of silicon nanowires were prepared by metal-catalyzed chemical vapor deposition on silicon substrates. Some of these ensembles were doped with phosphorous during growth. The nanowires were characterized using scanning electron microscopy, X-ray diffraction, and mass spectroscopy. Field emission of electrons from these structures was...
Transient magnetotransport of two-dimensional electrons with partially inverted distribution excited by an ultrashort optical pulse is studied theoretically. The time-dependent photoconductivity is calculated for GaAs-based quantum wells by taking into account the relaxation of the electron distribution caused by nonelastic electron-phonon interact...
We consider transient conductivity of electrons with partially inverted distribution created in the conduction band after an ultrafast interband photogeneration. The time-dependent photoconductivity is calculated for GaAs and InSb semiconductors taking into account the retardation of the response due to electron momentum relaxation. It is found tha...
Time-dependent current of the electrons excited in the conduction band after ultrafast interband photogeneration is studied theoretically. The transient photocurrent is calculated for the nonlinear regime of response to a stationary electric field. The response demonstrates transient absolute negative conductivity when the electrons are excited sli...
This lecture-style monograph is addressed to several categories of readers. First, it will be useful for graduate students studying theory. Second, the topics covered should be interesting for postgraduate students of various specializations. Third, the researchers who want to understand the background of modern theoretical issues in more detail ca...
The description of transport phenomena under conditions far from equilibrium requires a more careful consideration for the systems with strong scattering, since both the reconstruction of energy spectrum and the distribution of quasiparticles have to be considered simultaneously. For these purposes, it is convenient to use the nonequilibrium diagra...
The dynamical equations for quantum systems, the Schroedinger equation for pure states and the density-matrix equation for mixed states, form the theoretical background for description of transport phenomena in systems with different kinds of elementary excitations (quasiparticles). Both single-particle formulation of these equations and many-parti...
To derive the general kinetic equations in the previous chapters, we did not employ the condition of homogeneity, except for Chapter 5, where the basis of phonon wave vectors was used in the initial equations. Nevertheless, in each concrete case, a detailed analysis has been carried out either for homogeneous systems, when the momentum (or quasimom...
A consistent consideration of transport phenomena for different types of vibrational modes in solids (the branches of phonon spectrum and the modes of electromagnetic field introduced in Secs. 6 and 3, respectively) should be based upon the formalism of second quantization. Below we introduce the density matrix for bosons and derive kinetic equatio...
Each system is characterized by a number of physical quantities, which are often described by their mean values obtained as a result of the averaging of the operators of these quantities according to Eq. (1.18). Such a description is of the main interest in physics, because these mean values are the observable values. Nevertheless, one can obtain a...
The transitions of electrons, or other quasiparticles, between the states belonging to different branches of energy spectrum are often met in transport theory and can be described with the use of coupled kinetic equations for the distribution functions of these quasiparticles. There are, however, the cases when this approach is not valid, because t...
The structure of the kinetic equation for the electrons interacting with bosons (phonons or photons) is similar to the one for the case of electron-impurity system considered in Chapter 2. However, a consideration of electron scattering with emission or absorption of bosons leads to a more sophisticated collision integral, because the Pauli princip...
In this chapter we consider some features of transport phenomena caused by the interaction between electrons. As in the previous chapters, the kinetic equation is derived here under the assumption of weak electron-electron interaction. One should take into account that there are important physical situations when this assumption is not valid, and t...
The evolution of the system excited by a high-frequency electromagnetic field can be investigated by averaging the statistical operator over the period of perturbation. Applying this approach to electrons, one can introduce the rate of photogeneration, which is proportional to the intensity of the radiation and describes electron redistribution bet...
Non-equilibrium states of the systems weakly coupled to a thermostat are well investigated because these systems are easily driven from equilibrium by relatively weak external fields. On the other hand, weakly coupled systems are usually described by means of kinetic equations, and this approach is developed below and in Chapters 4–7. In this chapt...
A magnetic field causes electrons to rotate in the plane perpendicular to this field. As a result (see Sec. 11), the anisotropy of the response along the field and in the plane perpendicular to the field appears, and the kinetic coefficients are modified considerably if the cyclotron frequency exceeds the relaxation rate. Further qualitative modifi...
The picture of collision-limited (diffusive) transport fails in many cases, as we have seen on the example of electron transport in magnetic fields; see Chapter 10. The other examples considered in this chapter are i) the ballistic transport under the conditions when the size of the sample is comparable to the mean free path length so that electron...
We study the spin-polarized tunneling current between independently contacted quantum wells under an in-plane magnetic field. The splitting of energy spectra of two-dimensional electrons due to both spin-orbit and Pauli interactions is taken into account. The line shape of the resonant peak of the tunneling current is described for both homogeneous...
We present a theoretical study of the ballistic conductance in electron waveguides created by deep mesa etching from quantum-well structures with a two-dimensional electron gas (2DEG) in the well. The widths of the waveguides are controlled by gate bias voltages. We consider three different cases: the etched waveguide is completely covered by a gat...
We study the ballistic conductance of electron waveguides created by lateral depletion of the two-dimensional (2D) electron gas caused by negatively biased split surface Schottky gates. The maximal number of resolved steps of the quantized conductance staircase and their temperature stability are examined as functions of slit width w, depth d of th...
Tunneling between two-dimensional electron layers, where electron states are split by spin due to spin-orbit interaction, is studied theoretically. The expression for the tunneling current is derived and evaluated. The linear tunneling conductance shows two Lorentz-like peaks corresponding to the resonance contribution of two spin-split states. The...