Related papers: Rippled state of double-layer quantum Hall systems
We study the magnetotransport properties of dual-gated graphene bilayers, in which the total density and layer density imbalance are independently controlled. As the bilayer is imbalanced we observe the emergence of a quantum Hall state…
We study intersubband spin density collective modes in double-layer quantum Hall systems at $\nu=2$ within the time-dependent Hartree-Fock approximation. We find that these intersubband spin density excitations may soften under…
Double-layer quantum Hall systems with spontaneous broken symmetry can exhibit a novel manybody quantum Hall effect due to the strong interlayer coherence. When the layer separation becomes close to the critical value, quantum fluctuations…
We present results of a study of double layer quantum Hall systems in which each layer has a high-index Landau level that is half-filled. Hartree-Fock calculations indicate that, above a critical layer separation, the system becomes…
We present details of earlier studies (Zheng et al, Phys. Rev. Lett. 78, 310 (1997) and Das Sarma et al, ibid 79, 917 (1997)) and additional new results on double-layer quantum Hall systems at a total filling \nu = 2 \nu_1, where a single…
Measurements in GaAs hole bilayers with unequal layer densities reveal a pronounced magneto-resistance hysteresis at the magnetic field positions where either the majority or minority layer is at Landau level filling factor one. At a fixed…
We consider three states which are likely to be realized in bi-layer quantum Hall systems at total Landau level filling fraction ${\nu_T}=1$. Two of these states may be understood as paired states. One can occur as an instability of a…
The collective modes of stripes in double layer quantum Hall systems are computed using the time-dependent Hartree-Fock approximation. It is found that, when the system possesses spontaneous interlayer coherence, there are two gapless…
In the quantum Hall regime, electronic correlations in double-layer two-dimensional electron systems are strong because the kinetic energy is quenched by Landau quantization. In this article we point out that these correlations are…
Twisted bilayer graphene offers a unique bilayer two-dimensional-electron system where the layer separation is only in sub-nanometer scale. Unlike Bernal-stacked bilayer, the layer degree of freedom is disentangled from spin and valley,…
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…
In the bilayer quantum Hall system, a spontaneously charge imbalance state appears at the ground energy level. Gap in the collective excitation energy makes it stable against decoherence in macroscopic level. This state behaves as a spin…
We study non-Abelian fractional quantum Hall state in double layer systems at total filling factor $1/2$. Recent progresses in two-dimensional van der Waals materials made it possible to explore the regime with very small interlayer…
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 Hall-plateau width and the activation energy were measured in the bilayer quantum Hall state at filling factor \nu=2, 1 and 2/3, by changing the total electron density and the density ratio in the two quantum wells. Their behavior are…
A two-layer system coupled via tunneling and with different carrier masses in each layer is investigated in the integer quantum Hall regime. Striking deviations of the one-layer Hall conductivity from the usual quantization are found, if…
Double-layer quantum Hall systems possess interlayer phase coherence at sufficiently small layer separations, even without interlayer tunneling. When interlayer tunneling is present, application of a sufficiently strong in-plane magnetic…
The co-presence of multiple Dirac bands in few-layer graphene leads to a rich phase diagram in the quantum Hall regime. Using transport measurements, we map the phase diagram of BN-encapsulated ABA-stacked trilayer graphene as a function…
We consider various exchange-driven electronic instabilities in semiconductor double-layer systems in the absence of any external magnetic field. We establish that there is no exchange-driven bilayer to monolayer charge transfer instability…
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…