Related papers: Hole weak anti-localization in a strained-Ge surfa…
InAs quantum well heterostructures are of considerable interest for mesoscopic device applications such as scanning probe and magnetic recording sensors, which require the channel to be close to the surface. Here we report on…
We report an experimental study of quantum point contacts defined in a high-quality strained germanium quantum well with layered electric gates. At zero magnetic field, we observe quantized conductance plateaus in units of 2$e^2/h$.…
We report on transport characteristics of field effect two-dimensional electron gases (2DEG) in 24 nm wide indium arsenide surface quantum wells. High quality single-subband magnetotransport with clear quantized integer quantum Hall…
We present low temperature magnetoconductivity measurements of a density-tunable and high mobility two-dimensional electron gas confined in the wide bandgap GaN/AlGaN system. We observed pronounced anti-localization minima in the low-field…
The strength of the Zeeman splitting induced by an applied magnetic field is an important factor for the realization of spin-resolved transport in mesoscopic devices. We measure the Zeeman splitting for a quantum point contact etched into a…
We demonstrate that a lightly-strained germanium channel ($\varepsilon_{//}$ = -0.41%) in an undoped Ge/Si$_{0.1}$Ge$_{0.9}$ heterostructure field effect transistor supports a 2D hole gas with mobility in excess of 1$\times$10$^{6}$…
We present the findings of the spin-dependent transport of the 2D holes in the p-type ultra-narrow self-assembled silicon quantum well (Si-QW) confined by the superconductor barriers on the n-type Si (100) surface. The Aharonov-Casher…
The transport properties of the two-dimensional system in HgTe-based quantum wells containing simultaneously electrons and holes of low densities are examined. The Hall resistance, as a function of perpendicular magnetic field, reveals an…
Using the Feynman diagram techniques, we derive the finite-temperature conductivity and magnetoconductivity formulas from the quantum interference and electron-electron interaction, for a three-dimensional disordered Weyl semimetal. For a…
The selective confinement of light holes (LHs) in a tensile-strained germanium (Ge) quantum well is studied by mapping the electronic structure of Ge$_{1-x}$Sn$_x$/Ge/Ge$_{1-x}$Sn$_x$ heterostructures as a function of Sn content, residual…
Relativistic effects influence the motion of charged particles in solids by intertwining spin and momentum. The resulting phenomena exhibit rich and intriguing properties that can unveil radically new quantum devices. In this context, the…
An argument is made on the existence of a low-temperature itinerant antiferromagnetic (AF) spin alignment, rather than persistent helical (PH), in the ground state of a two dimensional electron gas in a semiconductor quantum well with…
The distribution of Coulomb blockade peak heights as a function of magnetic field is investigated experimentally in a Ge-Si nanowire quantum dot. Strong spin-orbit coupling in this hole-gas system leads to antilocalization of Coulomb…
Buried-channel semiconductor heterostructures are an archetype material platform to fabricate gated semiconductor quantum devices. Sharp confinement potential is obtained by positioning the channel near the surface, however nearby surface…
We look at the magnetic field induced weak localisation peak of graphene samples with different mobilities. At very low temperatures, low mobility samples exhibit a very broad peak as a function of the magnetic field, in contrast to higher…
With a view to electrical spin manipulation and quantum computing applications, recent significant attention has been devoted to semiconductor hole systems, which have very strong spin-orbit interactions. However, experimentally measuring,…
A two-dimensional gas of non-interacting quasiparticles in a nearly periodic potential and a perpendicular magnetic field is studied. The potential is a superposition of a periodic potential, induced e.g. by a charge density wave or a…
A variational theory is presented of A$^{1-}$ and A$^{2-}$ centers, i.e. of a negative acceptor ion localizing one and two conduction electrons, respectively, in a GaAs/GaAlAs quantum well in the presence of a magnetic field parallel to the…
We investigate the spin-polarized transport properties of a two-dimensional electron gas in a n-type diluted magnetic narrow gap semiconductor quantum well subjected to a perpendicular magnetic and electric field. Interesting beating…
Magneto-transport properties of a two-dimensional electron gas in a chain of planar quantum rings are investigated under the Rashba spin-orbit interaction and a transverse homogeneous magnetic field. A modulation potential function models…