Related papers: NMR Evidence for Spin Canting in a Bilayer nu = 2 …
We propose a model of spin-polarized-current state for electrons in bilayer graphene. The model resolves the puzzles as revealed by experiments that (a) the energy gap $E_{\rm gap}$ of the insulating ground state at the charge neutrality…
We have measured the Hall-plateau width and the activation energy of the bilayer quantum Hall (BLQH) states at the Landau-level filling factor $\nu=1$ and 2 by tilting the sample and simultaneously changing the electron density in each…
The nuclear-to-electron spin angular momentum conversion via hyperfine coupling in a normal metal (NM)/ferromagnet (FM) bilayer system is theoretically investigated by using the nonequilibrium Green's function method. The spin current…
We use high-mobility bilayer hole systems with negligible tunneling to examine how the bilayer nu = 1 quantum Hall state evolves as charge is transferred from one layer to the other at constant total density. We map bilayer nu = 1 state…
We study the fractional quantum Hall effect in a bilayer with charge-distribution imbalance induced, for instance, by a bias gate voltage. The bilayer can either be intrinsic or it can be formed spontaneously in wide quantum wells, due to…
We study the formation and characteristics of "spin droplets",i.e., compact spin-polarized configurations in the highest occupied Landau level, in an etched quantum Hall device at filling factors $2\leq\nu\leq3$. The confining potential for…
We report an electronic magnetization measurement of a quantum point contact (QPC) based on nuclear magnetic resonance (NMR) spectroscopy. We find that NMR signals can be detected by measuring the QPC conductance under in-plane magnetic…
We consider a fully spin-polarized quantum Hall system with no interlayer tunneling at total filling factor $\nu=1/k$ (where $k$ is an odd integer) using the Chern-Simons-Ginzburg-Landau theory. Exploiting particle-vortex duality and the…
Coherent oscillations between any two levels from four nuclear spin states of I=3/2 have been demonstrated in a nanometre-scale NMR semiconductor device, where nuclear spins are all-electrically controlled. Using this device, we discuss…
Nuclear spins are an important source of dephasing for electron spin qubits in GaAs quantum dots. Most studies of their dynamics have focused on the relatively slow longitudinal polarization. We show, based on a semiclassical model and…
The suppression of magnetic order and the detection of a half-quantized thermal Hall effect in {\alpha}-RuCl3 under an external magnetic field have sparked significant debate, whether these phenomena point to spin fractionalization, as…
Near to filling fraction $\nu=1$, the quantum Hall ferromagnet contains multiple Skyrmion spin excitations. This multi-Skyrmion system has a tremendously rich quantum-critical structure. This is simplified when Skyrmions are pinned by…
We propose localization measures in phase space of the ground state of bilayer quantum Hall (BLQH) systems at fractional filling factors $\nu=2/\lambda$, to characterize the three quantum phases (shortly denoted by spin, canted and ppin)…
We report measurements of spin pumping and the inverse spin Hall effect in Ni80Fe20/Uranium bilayers designed to study the efficiency of spin-charge interconversion in a super-heavy element. We employ broad-band ferromagnetic resonance on…
Based on the construction of generalized Halperin wave functions, we predict the possible existence of a large class of broken spin symmetry states in bilayer quantum Hall structures, generalizing the recently suggested canted…
Composite fermion metal states emerge in quantum Hall bilayers at total Landau level filling factor $\nu_T$=1 when the tunneling gap collapses by application of in-plane components of the external magnetic field. Evidence of this…
The longitudinal resistivity at transitions between integer quantum Hall states in two-dimensional electrons confined to AlAs quantum wells is found to depend on the spin orientation of the partially-filled Landau level in which the Fermi…
It is pointed out recently that the $\nu=1/m$ quantum Hall states in bilayer systems behave like easy plane quantum ferromagnets. We study the magnetotransport of these systems using their ``ferromagnetic" properties and a novel spin-charge…
In a Bernal-stacked graphene bilayer, an electronic state in Landau level $% N=0$ is described by its guiding-center index $X$ (in the Landau gauge) and by its valley, spin, and orbital indices $\xi =\pm K,\sigma =\pm 1,$ and $% n=0,1.$…
Dirac semimetals provide a new platform for the quantum Hall effect at low magnetic fields. In the presence of strong spin-orbit coupling, a spin-split Landau level is expected to enhance the bulk quasiparticle excitation. Here we report…