Related papers: Quantum Hall Andreev Conversion in Graphene Nanost…
This is a colloquium-style introduction to two electronic processes in a carbon monolayer (graphene), each having an analogue in relativistic quantum mechanics. Both processes couple electron-like and hole-like states, through the action of…
We demonstrate the emergence of novel topological phases in quantum Hall-superconductor hybrid systems driven by Landau level mixing and spin-orbit interactions. Focusing on a narrow superconducting stripe atop a two-dimensional electron…
We study the edge transport properties of paired fractional quantum Hall (FQH) states--- the Haldane-Rezayi (HR), Moore-Read (Pfaffian) and Halperin (331) states. A table of exponents is given for the tunneling between the edges of paired…
Indium Arsenide (InAs) near surface quantum wells (QWs) are promising for the fabrication of semiconductor-superconductor heterostructures given that they allow for a strong hybridization between the two-dimensional states in the quantum…
In this article, we study the transport properties of Graphene-Superconductor-Graphene (GSG) heterojunction where the superconducting region is created in the middle of a graphene sheet, as contrasted to widely studied transport properties…
Two-dimensional systems that host one-dimensional helical states are exciting from the perspective of scalable topological quantum computation when coupled with a superconductor. Graphene is particularly promising for its high electronic…
Quantum Hall edge states offer avenues for quasiparticle interferometry, provided that the ratio between phase coherence length and quantum Hall interferometer (QHI) size is large enough. Maximizing this ratio by shrinking the QHI area…
Quantum Hall (QH) and quantum spin Hall (QSH) phases have very different edge states and, when going from one phase to the other, the direction of one edge state must be reversed. We study this phenomena in graphene in presence of a strong…
Quantum Hall effects offer a formidable playground for the investigation of quantum transport phenomena. Edge modes can be detected, branched, and mixed by designing a suitable potential landscape in a two-dimensional conducting system…
We establish an analogy between superconductor-metal interfaces and the quantum physics of a black hole, using the proximity effect. We show that the metal-superconductor interface can be thought of as an event horizon and Andreev…
Transparent contact interfaces in superconductor-graphene hybrid systems are critical for realizing superconducting quantum applications. Here, we examine the effect of the edge-contact fabrication process on the transparency of the…
While usual edge states in the quantum Hall effect(QHE) reside between adjacent Landau levels, QHE in graphene has a peculiar edge mode at E=0 that reside right within the n=0 Landau level as protected by the chiral symmetry. We have…
We experimentally investigate electron transport through the interface between a superconductor and the edge of a two-dimensional electron system with band inversion. The interface is realized as a tunnel NbN side contact to a narrow 8~nm…
Extensive efforts have been undertaken to combine superconductivity and the quantum Hall effect so that Cooper-pair transport between superconducting electrodes in Josephson junctions is mediated by one-dimensional edge states. This…
Landau level bending near the edge of graphene, described using 2d Dirac equation, provides a microscopic framework for understanding the quantum Hall Effect (QHE) in this material. We review properties of the QHE edge states in graphene,…
We report on transport measurements of dual-gated, single-layer graphene devices in the quantum Hall regime, allowing for independent control of the filling factors in adjoining regions. Progress in device quality allows us to study…
We present an experimental study of inverted InAs/GaSb composite quantum wells in the hybridization regime and contacted by superconducting electrodes. A front gate is used to vary the Fermi level into the mini-gap, where recent experiments…
We report on Andreev reflections at clean NbSe2-bilayer graphene junctions. The high transparency of the junction, which manifests as a large conductance enhancement of up to 1.8, enables us to see clear evidence of a proximity-induced…
With low-buckled structure for each layer in graphene bilayer system, there breaks inversion symmetry (P-symmetry) for one stacking when both A and B sublattices in top layer are aligned with those in bottom layer. In consideration of…
We study crossed Andreev reflection (CAR) of electrons or holes in normal metal-superconductor-normal metal junctions and highlight some very strong effects of the underlying lattice. In particular, we demonstrate that for sharp interfaces…