Related papers: Strain-induced Fermi contour anisotropy of GaAs 2D…
We report measurements of spin susceptibility of a two-dimensional hole gas confined at an GaAs/AlGaAs interface in density range from 2.8 x 10^10 to 6.5 x 10^10 cm-2. We used the method of spin polarization of carriers in parallel magnetic…
Coupling the spin degree of freedom to the anisotropic orbital motion of two-dimensional (2D) hole systems gives rise to a highly anisotropic Zeeman splitting with respect to different orientations of an in-plane magnetic field B relative…
We show that in the metallic phase of a two dimensional electron gas the spin-orbit coupling due to structure inversion asymmetry leads to a characteristic anisotropy in the magnetoconductance. Within the assumption that the metallic phase…
We determine the anisotropy of the spin fluctuation induced pairing gap on the Fermi surface of the FeAs based superconductors as function of the exchange and Hund's coupling $J_{H}$. We find that for sufficiently large $J_{H}$, nearly…
We report the observation of a new phenomenon of colossal magnetoresistance in a 40 nm wide GaAs quantum well in the presence of an external magnetic field applied parallel to the high-mobility 2D electron layer. In a strong magnetic field,…
In ultra-clean 2D electron systems on (001) GaAs/AlGaAs upon filling high Landau levels, it was recently observed a new class of collective states, which can be related to the spontaneous formation of a charge density wave (``striped…
The effect of strong anisotropy on the Fermi line of a system of correlated electrons is studied in two space dimensions, using renormalization group techniques. Inflection points change the scaling exponents of the couplings, enhancing the…
We report effective hole mass ($m^{*}$) measurements through analyzing the temperature dependence of Shubnikov-de Haas oscillations in dilute (density $p \sim 7 \times 10^{10}$ cm$^{-2}$, $r_{s} \sim 6$) two-dimensional (2D) hole systems…
Experiments on resonances of conduction electrons in InGaAs/InAlAs double quantum wells at megagauss magnetic fields in the Faraday geometry are reported. We observe new cyclotron resonances assisted by emission of InAs-like and GaAs-like…
We present observations of an anisotropic resistance state at Landau level filling factor $\nu=5/2$ in a two-dimensional hole system (2DHS), which occurs for certain values of hole density $p$ and average out-of-plane electric field…
InAs/GaSb hosts a broken gap band alignment that has been shown to generate helical topological edge states. Upon the introduction of Mn into the structure, it has been predicted to host a quantized anomalous Hall effect. Here, we show that…
The complex structure of the valence band in many semiconductors leads to multifaceted and unusual properties for spin-3/2 hole systems compared to typical spin-1/2 electron systems. In particular, two-dimensional hole systems show a highly…
In time-resolved Faraday rotation experiments we have detected an inplane anisotropy of the electron spin-dephasing time (SDT) in an $n$--modulation-doped GaAs/Al$_{0.3}$Ga$_{0.7}$As single quantum well. The SDT was measured with magnetic…
We demonstrate how shape-induced strain can be used to control antiferromagnetic order in NiO/Pt thin films. For rectangular elements patterned along the easy and hard magnetocrystalline anisotropy axes of our film, we observe different…
We have studied quantum-well-confined holes based on the Luttinger-model description for the valence band of typical semiconductor materials. Even when only the lowest quasi-two-dimensional (quasi-2D) subband is populated, the static spin…
Spin relaxation can be greatly enhanced in narrow channels of two-dimensional electron gas due to ballistic spin resonance, which is mediated by spin-orbit interaction for trajectories that bounce rapidly between channel walls. The channel…
We report ballistic transport measurements in a two-dimensional electron system confined to an AlAs quantum well and patterned with square antidot lattices of period $a = $0.6, 0.8, 1.0 and 1.5 $\mu$m. In this system two in-plane…
We report Shubnikov-de Haas oscillations measurements revealing experimental signatures of an annular Fermi sea that develops near the energy band edge of the excited subband of two-dimensional holes confined in a wide GaAs quantum well. As…
It is demonstrated by SQUID magnetization measurements that (Ga,Mn)As films can exhibit rich characteristics of magnetic anisotropy depending not only to the epitaxial strain but being strongly influenced by the hole and Mn concentration,…
g-factor tuning of electrons in quantum dots is studied as function of in-plane and perpendicular magnetic fields for different confinements. Rashba and Dresselhaus effects are considered, and comparison is made between wide- and narrow-gap…