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arXiv · 1703.03699

Zero-Energy Modes from Coalescing Andreev States in a Two-Dimensional Semiconductor-Superconductor Hybrid Platform

Henri J. Suominen·Morten Kjaergaard·Alexander R. Hamilton·Javad Shabani·Chris J. Palmstrøm·Charles M. Marcus·Fabrizio Nichele
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Abstract

We investigate zero-bias conductance peaks that arise from coalescing subgap Andreev states, consistent with emerging Majorana zero modes, in hybrid semiconductor-superconductor wires defined in a two-dimensional InAs/Al heterostructure using top-down lithography and gating. The measurements indicate a hard superconducting gap, ballistic tunneling contact, and in-plane critical fields up to $3$~T. Top-down lithography allows complex geometries, branched structures, and straightforward scaling to multicomponent devices compared to structures made from assembled nanowires.

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Henri J. Suominen, Morten Kjaergaard, Alexander R. Hamilton, Javad Shabani, Chris J. Palmstrøm, Charles M. Marcus, Fabrizio Nichele. 2017-10-27. Zero-Energy Modes from Coalescing Andreev States in a Two-Dimensional Semiconductor-Superconductor Hybrid Platform. https://doi.org/10.1103/physrevlett.119.176805

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