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arXiv · 1904.10132

Realization of a Carbon-Nanotube-Based Superconducting Qubit

Matthias Mergenthaler·Ani Nersisyan·Andrew Patterson·Martina Esposito·Andreas Baumgartner·Christian Schönenberger·G. Andrew D. Briggs·Edward A. Laird·Peter J. Leek
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Abstract

Hybrid circuit quantum electrodynamics (QED) involves the study of coherent quantum physics in solid state systems via their interactions with superconducting microwave circuits. Here we present an implementation of a hybrid superconducting qubit that employs a carbon nanotube as a Josephson junction. We realize the junction by contacting a carbon nanotube with a superconducting Pd/Al bi-layer, and implement voltage tunability of the qubit frequency using a local electrostatic gate. We demonstrate strong dispersive coupling to a coplanar waveguide resonator via observation of a resonator frequency shift dependent on applied gate voltage. We extract qubit parameters from spectroscopy using dispersive readout and find qubit relaxation and coherence times in the range of $10-200~\rm{ns}$.

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Matthias Mergenthaler, Ani Nersisyan, Andrew Patterson, Martina Esposito, Andreas Baumgartner, Christian Schönenberger, G. Andrew D. Briggs, Edward A. Laird, Peter J. Leek. 2019-04-23. Realization of a Carbon-Nanotube-Based Superconducting Qubit. https://doi.org/10.1103/physrevapplied.15.064050

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