Loss and Decoherence at the Quantum Hall-Superconductor Interface.

We perform a systematic study of Andreev conversion at the interface between a superconductor and graphene in the quantum Hall (QH) regime. We find that the probability of Andreev conversion from electrons to holes follows an unexpected but clear trend: the dependencies on temperature and magnetic field are nearly decoupled. We discuss these trends and the role of the superconducting vortices, whose normal cores could both absorb and dephase the individual electrons in a QH edge.

Paris or Berlin? Claude Bernard's rivalry with Emil du Bois-Reymond.

Claude Bernard (1813-1878) and Emil du Bois-Reymond (1818-1896) rank as two of the most influential scientists of the nineteenth century. Renowned for their experiments, lectures, and writing, Bernard and du Bois-Reymond earned great prestige as professors of physiology in a time when Paris and Berlin reigned as capitals of science. Yet even though they were equals in every way, du Bois-Reymond's reputation has fallen far more than Bernard's.

Anisotropic superconductivity at KTaO(111) interfaces.

A two-dimensional, anisotropic superconductivity was recently found at the KTaO(111) interfaces. The nature of the anisotropic superconducting transition remains a subject of debate. To investigate the origins of the observed behavior, we grew epitaxial KTaO(111)-based heterostructures.

Graphene-Based Quantum Hall Interferometer with Self-Aligned Side Gates.

The vanishing band gap of graphene has long presented challenges for making high-quality quantum point contacts (QPCs)─the partially transparent p-n interfaces introduced by conventional split gates tend to short circuit the QPCs. This complication has hindered the fabrication of graphene quantum Hall Fabry-Pérot interferometers, until recent advances have allowed split-gate QPCs to operate utilizing the highly resistive ν = 0 state. Here, we present a simple recipe to fabricate QPCs by etching a narrow trench in the graphene sheet to separate the conducting channel from self-aligned graphene side gates.