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arXiv · 1902.00789

Radio-frequency methods for Majorana-based quantum devices: fast charge sensing and phase diagram mapping

Davydas Razmadze·Deividas Sabonis·Filip K. Malinowski·Gerbold C. Menard·Sebastian Pauka·Hung Nguyen·David M. T. van Zanten·Eoin C. T. O'Farrell·Judith Suter·Peter Krogstrup·Ferdinand Kuemmeth·Charles M. Marcus
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Abstract

Radio-frequency (RF) reflectometry is implemented in hybrid semiconductor-superconductor nanowire systems designed to probe Majorana zero modes. Two approaches are presented. In the first, hybrid nanowire-based devices are part of a resonant circuit, allowing conductance to be measured as a function of several gate voltages ~40 times faster than using conventional low-frequency lock-in methods. In the second, nanowire devices are capacitively coupled to a nearby RF single-electron transistor made from a separate nanowire, allowing RF detection of charge, including charge-only measurement of the crossover from 2e inter-island charge transitions at zero magnetic field to 1e transitions at axial magnetic fields above 0.6 T, where a topological state is expected. Single-electron sensing yields signal-to-noise exceeding 3 and visibility 99.8% for a measurement time of 1 μs.

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Davydas Razmadze, Deividas Sabonis, Filip K. Malinowski, Gerbold C. Menard, Sebastian Pauka, Hung Nguyen, David M. T. van Zanten, Eoin C. T. O'Farrell, Judith Suter, Peter Krogstrup, Ferdinand Kuemmeth, Charles M. Marcus. 2019-02-02. Radio-frequency methods for Majorana-based quantum devices: fast charge sensing and phase diagram mapping. https://doi.org/10.1103/physrevapplied.11.064011

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