相关论文: RK/100 and RK/200 Quantum Hall Array Resistance St…
This paper reports on an experimental study of the contact resistance of Hall bars in the Quantum Hall Effect regime while increasing the current through the sample. These measurements involve also the longitudinal resistance and they have…
The use of multiple current terminals on millimeter-scale graphene $p-n$ junction devices fabricated with Corbino geometries, or quantum Hall resistance dartboards, have enabled the measurement of several fractional multiples of the…
The quantum Hall effect (QHE) is a topologically protected phenomenon which has been observed in various systems. In experiments, the size of Hall bar device to realize the QHE is generally much larger than the phase coherence length, in…
Evidence of both fractional and integer quantum hall effects (QHE) in three dimensional bulk replica opal (250nm diameter) structures of non-crystalline carbon are presented. In a remarkably soft quantum limit of ~ 40K temperature and about…
We have observed quantization of the diagonal resistance, R_xx, at the edges of several quantum Hall states. Each quantized R_xx value is close to the difference between the two adjacent Hall plateaus in the off-diagonal resistance, R_xy.…
We develop a theory of edge state transport in separately contacted double-layer quantum Hall systems which are tuned close to the resonance condition for tunneling between the layers. When applied to the case where contact is made to only…
In the quantum Hall regime the charge current is carried by ideal one-dimensional edge channels where the backscattering is prohibited by topology. This results in the constant potential along the edge of the Hall bar leading to zero…
We demonstrate quantum Hall resistance measurements with metrological accuracy in a small cryogen-free system operating at a temperature of around 3.8K and magnetic fields below 5T. Operating this system requires little experimental…
In the quantum anomalous Hall effect, quantized Hall resistance and vanishing longitudinal resistivity are predicted to result from the presence of dissipationless, chiral edge states and an insulating 2D bulk, without requiring an external…
We report magnetotransport measurements on a single-layer graphene in pulsed magnetic fields up to $B$ = 53 T. With either electron- or hole-type charge carriers, the Hall resistance $R_{H}$ is quantized into $R_{H}$ = $(h/e^2)\nu ^{-1}$…
We analyze electron transport in multiprobe quantum spin Hall (QSH) bars using the B\"{u}ttiker formalism and draw parallels with their quantum Hall (QH) counterparts. We find that in a QSH bar the measured resistance changes upon…
The quantum anomalous Hall (QAH) effect holds fundamental importance in topological physics and technological promise for electronics. It is generally believed that the QAH effect can only be realized in insulators. In this Letter, we…
We have conducted an experimental study of the linear transport properties of the magnetic-field induced insulating phase which terminates the quantum Hall (QH) series in two dimensional electron systems. We found that a direct and simple…
In quantum anomalous Hall (QAH) insulators, the interior is insulating but electrons can travel with zero resistance along one-dimensional conducting paths known as chiral edge channels (CECs). These CECs have been predicted to be confined…
Our microscopic understanding of the integer quantum Hall effect is still incomplete. For decades, there has been a controversial discussion about "where the current flows" if the Hall resistance is quantized. Here, we qualitatively analyze…
Transport measurements were made on four-terminal devices fabricated from InSb/Al_xIn_(1-x)Sb quantum well structures at temperatures from 1.5 to 300K. Negative bend resistance, which is characteristic of ballistic transport, was observed…
Properties of one-dimensional (1D) arrays of low Ohmic tunnel junctions (i.e. junctions with resistances comparable to, or less than, the quantum resistance $R_{\rm q}\equiv h/e^2\approx 25.8$ k$\Omega$) have been studied experimentally and…
We show that in the limit of zero temperature, double layer quantum Hall systems exhibit a novel phenomena called Hall drag, namely a current driven in one layer induces a voltage drop in the other layer, in the direction perpendicular to…
We report the observation of an even-denominator fractional quantum Hall (FQH) state at $\nu=1/4$ in a high quality, wide GaAs quantum well. The sample has a quantum well width of 50 nm and an electron density of $n_e=2.55\times10^{11}$…
It is well established that the ground states of a two-dimensional electron gas with half-filled high ($N \ge 2$) Landau levels are compressible charge-ordered states, known as quantum Hall stripe (QHS) phases. The generic features of QHSs…