相关论文: SU(4) Coherent Effects to the Canted Antiferromagn…
We study the quantum Hall effect in graphene at filling factors \nu = 0 and \nu = \pm, concentrating on the quantum Hall ferromagnetic regime, within a non-perturbative bosonization formalism. We start by developing a bosonization scheme…
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…
We report on an exact diagonalization study of fractional quantum Hall states at filling factor $\nu=2/3$ in a system with a four-fold degenerate $n$=0 Landau level and SU(4) symmetric Coulomb interactions. Our investigation reveals…
Bilayer quantum Hall (BLQH) systems, which underlie a $U(4)$ symmetry, display unique quantum coherence effects. We study coherent states (CS) on the complex Grassmannian $\mathbb G_2^4=U(4)/U(2)^2$, orthonormal basis, $U(4)$ generators and…
A two-dimensional electron system exposed to a strong magnetic field produces a plethora of strongly interacting fractional quantum Hall (FQH) states, the complex topological orders of which are revealed through exotic emergent particles,…
The most celebrated property of the quantum spin Hall effect is the presence of spin-polarized counter-propagating edge states. This novel edge state configuration has also been predicted to occur in graphene when spin-split electron- and…
In this paper we study in detail different types of topological solitons which are possible in bilayer quantum Hall systems at filling fraction $\nu =1$ when spin degrees of freedom are included. Starting from a microscopic Hamiltonian we…
We present a phase diagram for a double quantum well bilayer electron gas in the quantum Hall regime at total filling factor $\nu =1$, based on exact numerical calculations of the topological Chern number matrix and the (inter-layer)…
We propose moir\'e bilayer as a platform where exotic quantum phases can be stabilized and electrically detected. Moir\'e bilayer consists of two separate moir\'e superlattice layers coupled through the inter-layer Coulomb repulsion. In the…
For sufficiently strong in-plane magnetic field a $\nu_T=1$ bilayer quantum Hall pseudo-ferromagnet is expected to exhibit a soliton lattice. For sufficiently close layers and large in-plane field, we predict this incommensurate ``planar''…
Using exact diagonalization of bilayer quantum Hall systems at total filling factor $\nu_T=1$ in the torus geometry, we show that there is a new long-range interlayer phase coherence due to spontaneous pseudospin spiral order at interlayer…
A "squeezed-vacuum" state considered in quantum optics is shown to be realized in the ground-state wavefunction for the bilayer quantum Hall system at the total Landau level filling of $\nu=1/m$ (m: odd integer). This is derived in the…
A bilayer system of two-dimensional electron gases in a perpendicular magnetic field exhibits rich phenomena. At total filling factor $\nu_{tot} = 1$, as one increases the layer separation, the bilayer system goes from an interlayer…
We present a microscopic study of the interlayer spacing d versus in-plane magnetic field $B_\parallel$ phase diagram for bilayer quantum Hall (QH) pseudo-ferromagnets. In addition to the interlayer charge balanced commensurate and…
We investigate a domain structure of pseudospins, a soliton lattice in the bilayer quantum Hall state at total Landau level filling factor $\nu =1$, in a tilted magnetic field, where the pseudospin represents the layer degree of freedom. An…
We analyze bilayer quantum Hall ferromagnets, whose underlying symmetry group is SU(4). Spin-pseudospin coherence develops spontaneously when the total electron density is low enough. Quasiparticles are CP^3 skyrmions. One skyrmion induces…
We investigate the feasibility of many candidate quantum Hall states for two-component bosons in the lowest Landau level. We identify interactions for which spin-singlet incompressible states occur at filling factors $\nu=2/3$, 4/5 and 4/3,…
At the filling factor $\nu=2$ the bilayer quantum Hall system has three phases, the ferromagnetic phase (spin phase), the spin singlet phase (ppin phase) and the canted antiferromagnetic phase. We analyze soft waves and quasiparticle…
Excitation spectra in bilayer quantum Hall systems at total Landau-level filling $\nu=2$ are studied by the Hartree-Fock-Bogoliubov approximation. The systems have the spin degrees of freedom in addition to the layer degrees of freedom…
Bilayer graphene, in the presence of a one-sided spin-orbit interaction (SOI) induced by a suitably chosen substrate, is predicted to exhibit unconventional Quantum Hall states. The new states arise due to strong SOI-induced splittings of…