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arXiv · 2005.09250

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
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Abstract

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

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Samuel Piotr Wolski, Dany Lachance-Quirion, Yutaka Tabuchi, Shingo Kono, Atsushi Noguchi, Koji Usami, Yasunobu Nakamura. 2020-05-19. Dissipation-based Quantum Sensing of Magnons with a Superconducting Qubit. https://doi.org/10.1103/physrevlett.125.117701

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