Quantum dot spectroscopy of proximity-induced superconductivity in a two-dimensional electron gas

Abstract

We report the realization of a hybrid superconductor-quantum dot device by means of top-down nanofabrication starting from a two dimensional electron gas in a InGaAs/InAlAs semiconductor heterostructure. The quantum dot is defined by electrostatic gates placed within the normal region of a planar Nb-InGaAs quantum well-Nb junction. Measurements in the regime of strong Coulomb blockade as well as cotunneling spectroscopy allow to directly probe the proximity-induced energy gap in a ballistic two-dimensional electron gas coupled to superconductors.

4 pages, 3 figures

References in corpus (8)

• Supercurrent reversal in quantum dots
• Phase controlled superconducting proximity effect probed by tunneling spectroscopy
• Critical Current 0-$\pi$ Transition in Designed Josephson Quantum Dot Junctions
• Even-odd effect in Andreev Transport through a Carbon Nanotube Quantum Dot
• Kondo-Enhanced Andreev Tunneling in InAs Nanowire Quantum Dots
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• Andreev reflection versus Coulomb blockade in hybrid semiconductor nanowire devices
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