Related papers: Effective mass suppression in dilute, spin-polariz…
The low-temperature($4.2<T<12.5$ K) magnetotransport ($B<2$ T) of two-dimensional electrons occupying two subbands (with energy $E_1$ and $E_2$) is investigated in GaAs single quantum well with AlAs/GaAs superlattice barriers. Two series of…
In a recent Letter (PRL 88, 196404 (2002)), the effective g-factor and the effective mass have been studied by Pudalov et al. in a dilute 2D electron system in silicon. The authors contrast their data with the data obtained by our group…
We introduce the concept of a spintronic effective mass for spin-polarized carriers in semiconductor structures, which arises from the strong spin-polarization dependence of the renormalized effective mass in an interacting spin-polarized…
The article shows a simple model that computes the magnetoconduction and the integer quantum Hall effect (IQHE) in a two-dimensional electron system (2DES) where the spin is other degree of freedom in the system. The 2DES is confined in a…
The energy spectrum of the conduction band in HgTe/Cd$_x$Hg$_{1-x}$Te quantum wells of a width $d=(4.6-20.2)$ nm has been experimentally studied in a wide range of electron density. For this purpose, the electron density dependence of the…
We studied the Shubnikov-de Haas (SdH) oscillations in high-mobility Si-MOS samples over a wide range of carrier densities $n\simeq (1-50) \times 10^{11}$cm$^{-2}$, which includes the vicinity of the apparent metal-insulator transition in…
We performed effective mass measurements employing microwave-induced resistance oscillation in a tunable-density GaAs/AlGaAs quantum well. Our main result is a clear observation of an effective mass increase with decreasing density, in…
We have performed microwave photoresistance measurements in high mobility GaAs/AlGaAs quantum wells and investigated the value of the effective mass. Surprisingly, the effective mass, obtained from the period of microwave-induced resistance…
We study the magnetotransport of high-mobility electrons in monolayer and bilayer MoSe$_2$, which show Shubnikov-de Haas (SdH) oscillations and quantum Hall states in high magnetic fields. An electron effective mass of 0.8$m_e$ is extracted…
Using a `standard' NMR spin-echo technique we determined the spin polarization of two-dimensional electrons, confined to GaAs quantum wells, from the hyperfine shift of Ga nuclei in the wells. Concentrating on the temperature and magnetic…
The magnetoresistance of a low carrier density, disordered GaAs based two-dimensional (2D) electron gas has been measured in parallel magnetic fields up to 32 T. The feature in the resistance associated with the complete spin polarization…
Recent experiments on two-dimensional (2D) electron systems have found a sharp increase in the effective mass of electrons with decreasing electron density. In an effort to understand this behavior we employ the many-body theory to…
We present theoretical aspects of spin polarized two dimensional electron gas (SP2DEG) which can be achieved in doped semimagnetic quantum wells. This original model system has been recently studied by magneto Raman scattering experiments…
The frequencies of Shubnikov-de Haas oscillations have long been used to measure the unequal population of spin-split two-dimensional subbands in inversion asymmetric systems. We report self-consistent numerical calculations and…
We report the observation of Shubnikov-de Haas (SdH) oscillations in coherently strained, low-dislocation AlN/GaN/AlN quantum wells (QWs), including both undoped and $\delta$-doped structures. SdH measurements reveal a single subband…
The interrelation between spin and charge in semiconductors leads to interesting effects, e.g., the Rashba-type spin-orbit splitting or the exchange enhancement. These properties are proposed to be used in applications such as spin…
We consider the magnetic response of a two-dimensional electron gas (2DEG) with a spin-orbit interaction to a long-wave-length electromagnetic excitation. We observe that the transverse electric field creates spin polarization perpendicular…
We report magneto-transport measurements on high-mobility two-dimensional electron systems (2DESs) confined in In_0.75Ga_0.25As/In_0.75Al_0.25As single quantum wells. Several quantum Hall states are observed in a wide range of temperatures…
We have made quantitative measurements of the spin polarization of two-dimensional (2D) GaAs (100) electrons and GaAs (311)A holes, as a function of an in-plane magnetic field. The functional form of the in-plane magnetoresistance is shown…
We report direct experimental evidence that the insulating phase of a disordered, yet strongly interacting two-dimensional electron system (2DES) becomes unstable at low temperatures. As the temperature decreases, a transition from…