Related papers: Tilt Induced Localization and Delocalization in th…
The helical edge states in a quantum spin Hall insulator are presumably protected by time- reversal symmetry. However, even in the presence of magnetic field which breaks time-reversal symmetry, the helical edge conduction can still exist,…
We demonstrate that the two-dimensonal electron system in a strong perpendicular magnetic field has stable states which break rotational but not translational symmetry. The Laughlin fluid becomes unstable to these states in quantum wells…
A quantum Hall system which is divided into two laterally coupled subsystems by means of a tunneling barrier exhibits a complex Landau level dispersion. Magnetotunneling spectroscopy is employed to investigate the small energy gaps which…
Motivated by the experimental observation of a quantized 5/2 thermal conductance at filling $\nu=5/2$, a result incompatible with both the Pfaffian and the Antipfaffian states, we have pushed the expansion of the effective Hamiltonian of…
We study two interacting electrons in a two-dimensional system under a strong magnetic field and show that their numerically exact solutions organize into a set of {\em sub-Landau levels} characterized by relative angular momentum quantum…
The mixing of states with {\it opposite chirality} in quantum Hall system is shown to have delocalization effect. It is possible that extended states may form bands because of this mixing, as is shown through a numerical calculation on a…
We study theoretically edge transport of a fractional quantum Hall liquid, in the presence of a quantum dot inside the Hall bar with well controlled electron density and Landau level filling factor \nu, and show that such transport studies…
Fractional quantum Hall states at a half-filled Landau level are believed to carry an integer number $\mathcal{C}$ of chiral Majorana edge modes, reflected in their thermal Hall conductivity. We show that this number determines the primary…
We study the coupled quantum Hall bilayers each at half-filled first excited Landau levels with varying the layer distance. Based on numerical exact diagonalization on torus, we identify two distinct phases separated by a critical layer…
The polarization and density modulation associated with antiferroelectric ordering is studied experimentally as a function of temperature in two ferroelectric nematic liquid crystals, the prototypical single compound (DIO) and a commercial…
Interesting non-Abelian states, e.g., the Moore-Read Pfaffian and the anti-Pfaffian, offer candidate descriptions of the $\nu = 5/2$ fractional quantum Hall state. But the significant controversy surrounding the nature of the $\nu = 5/2$…
Transport measurements under a tilted magnetic field were performed on a series of C-doped (001) AlGaAs/GaAs/AlGaAs two-dimensional hole samples. Due to a large g-factor, Zeeman energy is large and comparable to the cyclotron energy in…
For the fast rotating quasi-two-dimensional dipolar fermions in the quantum Hall regime, the interaction between two dipoles breaks the rotational symmetry when the dipole moment has component in the the plane via being tuned by an external…
We report on exact diagonalization studies for fully spin polarized 5/2 fractional quantum Hall effect, incorporating Landau level mixing through the Bishara-Nayak effective interaction. We find that there is an experimentally accessible…
We have studied the $\nu=5/2$ fractional quantum Hall state in a density-tunable sample at extremely low electron densities. For the densities accessed in our experiment, the Landau level mixing parameter $\kappa$ spans the…
Two-dimensional systems in magnetic fields host rich physics, most notably the quantum Hall effect arising from Landau level quantization. In a broad class of two-dimensional models, flat bands with topologically nontrivial band…
A single Landau level (LL) dressed with periodic electrostatic potentials can realize a plethora of interacting topological phases where the Hall conductivity generally does not equal to the LL filling factor. Their physics can be captured…
We present longitudinal and Hall magneto-resistance measurements of a ``magnetic'' two-dimensional electron gas (2DEG) formed in modulation-doped Zn$_{1-x-y}$Cd$_{x}$Mn$_{y}$Se quantum wells. The electron spin splitting is temperature and…
The physical properties of striped Hall state in the presence of an external unidirectional periodic potential is investigated. The study of searching the optimal orientation of the state is reported for the state at filling factor…
Magnetic fields quench the kinetic energy of two dimensional electrons, confining them to highly degenerate Landau levels. In the absence of disorder, the ground state at partial Landau level filling is determined only by Coulomb…