相关论文: Landau level transitions in InAs/AlSb/GaSb quantum…
Transport measurements are performed on InAs/GaSb double quantum wells at zero and finite magnetic fields applied parallel and perpendicular to the quantum wells. We investigate a sample in the inverted regime where electrons and holes…
We have studied a series of InAs/GaSb coupled quantum wells using magneto-infrared spectroscopy for high magnetic fields up to 33T within temperatures ranging from 4K to 45K in both Faraday and tilted field geometries. This type of coupled…
We present magnetotransport measurements of a strongly hybridized inverted InAs/GaSb double quantum well. We find that the spin-orbit interaction leads to an appreciable spin-splitting of hole-like states, which form distinct Landau levels…
We have studied the optical and electrical spectra from an n i p LED as a function of magnetic field. This sample incorporated three GaAs quantum wells in the intrinsic region. This device had excess n type doping and as a result. The…
InAs-AlSb quantum wells are investigated by transport experiments in magnetic fields tilted with respect to the sample normal. Using the coincidence method we find for magnetic fields up to 28 T that the spin splitting can be as large as 5…
Subband structure and depolarization shifts in an ultra-high mobility GaAs/Al_{0.24}Ga_{0.76}As quantum well are studied using magneto-infrared spectroscopy via resonant subband Landau level coupling. Resonant couplings between the 1st and…
We studied InSb quantum well devices using Landau level tunneling spectroscopy through a three-terminal differential conductance technique. This method is similar to filled state scanning tunneling microscopy but uses a stationary contact…
HgTe/HgCdTe quantum wells with the inverted band structure have been probed using far infrared magneto-spectroscopy. Realistic calculations of Landau level diagrams have been performed to identify the observed transitions. Investigations…
We report measurements of the quantum Hall state energy gap at avoided crossings between Landau levels originating from different conduction band valleys in AlAs quantum wells. These gaps exhibit an approximately linear dependence on…
Oscillations of the real component of AC conductivity $\sigma_1$ in a magnetic field were measured in the n-AlGaAs/GaAs structure with a wide (75 nm) quantum well by contactless acoustic methods at $T$=(20-500)~mK. In a wide quantum well,…
Two laterally adjacent quantum Hall systems separated by an extended barrier of a thickness on the order of the magnetic length possess a complex Landau band structure in the vicinity of the line junction. The energy dispersion is obtained…
We study a $Al_{x}Ga_{x-1}As$ parabolic quantum wells (PQW) with $GaAs/Al_{x}Ga_{x-1}As$ square superlattice. The magnetotransport in PQW with intentionally disordered short-period superlattice reveals a surprising transition from electrons…
In wide GaAs quantum wells where two electric subbands are occupied we apply a parallel magnetic field or increase the electron density to cause a crossing of the two $N=0$ Landau levels of these subbands and with opposite spins. Near the…
We present both the experimental and theoretical investigation of a non-trivial electron Landau levels shift in magnetic field in wide ~20 nm HgTe quantum wells: Landau levels split under magnetic fields but become degenerate again when…
Mainstream among topological insulators, GaSb/InAs quantum wells present a broken gap alignment for the energy bands which supports the quantum spin Hall insulator phase and forms an important building block in the search of exotic states…
The cross-over from quasi-two- to quasi-one-dimensional electron transport subject to transverse electric fields and perpendicular magnetic fields are studied in the diffusive to quasiballistic and zero-field to quantum Hall regime.…
Quantum oscillations of nonlinear resistance are investigated in response to electric current and magnetic field applied perpendicular to single GaAs quantum wells with two populated subbands. At small magnetic fields current-induced…
The quantum spin Hall effect has been predicted theoretically and observed experimentally in InAs/GaSb quantum wells as a result of inverted band structures, for which electron bands in InAs layers are below heavy hole bands in GaSb layers…
We study two dimensional electron systems confined in wide quantum wells whose subband separation is comparable with the Zeeman energy. Two N = 0 Landau levels from different subbands and with opposite spins are pinned in energy when they…
Electron-hole hybridization in InAs/GaSb double quantum well structures leads to the formation of a mini band gap. We experimentally and theoretically studied the impact of strain on the transport properties of this material system. Thinned…