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arXiv · 1405.6648

A ballistic two-dimensional-electron-gas Andreev interferometer

M. Amado·A. Fornieri·G. Biasiol·L. Sorba·F. Giazotto
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Abstract

We report the realization and investigation of a ballistic Andreev interferometer based on an InAs two dimensional electron gas coupled to a superconducting Nb loop. We observe strong magnetic modulations in the voltage drop across the device due to quasiparticle interference within the weak-link. The interferometer exhibits flux noise down to $\sim 80\, μΦ_0/\sqrt{\textrm{Hz}}$, and a robust behavior in temperature with voltage oscillations surviving up to $\sim7\,$K. Besides this remarkable performance, the device represents a crucial first step for the realization of a fully-tunable ballistic superconducting magnetometer and embodies a potential new platform for the investigation of Majorana bound states as well as non-local entanglement of Cooper pairs.

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M. Amado, A. Fornieri, G. Biasiol, L. Sorba, F. Giazotto. 2014-06-10. A ballistic two-dimensional-electron-gas Andreev interferometer. https://doi.org/10.1063/1.4884952

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