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Dissipation-based Quantum Sensing of Magnons with a Superconducting Qubit

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 نشر من قبل Samuel Wolski
 تاريخ النشر 2020
  مجال البحث فيزياء
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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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