arXiv:2005.09250 · Physical Review Letters

Dissipation-Based Quantum Sensing of Magnons with a Superconducting Qubit

Samuel Piotr Wolski, Dany Lachance-Quirion, Yutaka Tabuchi, Shingo Kono, Atsushi Noguchi, Koji Usami, Yasunobu Nakamura

Published Sep 8, 2020• 170 citations

Abstract

Hybrid quantum devices expand the tools and techniques available for quantum sensing in various fields. Here, we experimentally demonstrate quantum sensing of a steady-state magnon population in a magnetostatic mode of a ferrimagnetic crystal. Dispersively coupling the magnetostatic mode to a superconducting qubit allows for the detection of magnons using Ramsey interferometry with a sensitivity on the order of 10^{-3} magnons/sqrt[Hz]. The protocol is based on dissipation as dephasing via fluctuations in the magnetostatic mode reduces the qubit coherence proportionally to the number of magnons.

DOI: 10.1103/physrevlett.125.117701

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