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arXiv · 1205.5659

Electron spin resonance detected by a superconducting qubit

Y. Kubo·I. Diniz·C. Grezes·T. Umeda·J. Isoya·H. Sumiya·T. Yamamoto·H. Abe·S. Onoda·T. Ohshima·V. Jacques·A. Dréau·J. -F. Roch·A. Auffeves·D. Vion·D. Esteve·P. Bertet
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Abstract

A new method for detecting the magnetic resonance of electronic spins at low temperature is demonstrated. It consists in measuring the signal emitted by the spins with a superconducting qubit that acts as a single-microwave-photon detector, resulting in an enhanced sensitivity. We implement this new type of electron-spin resonance spectroscopy using a hybrid quantum circuit in which a transmon qubit is coupled to a spin ensemble consisting of NV centers in diamond. With this setup we measure the NV center absorption spectrum at 30mK at an excitation level of \thicksim15\,μ_{B} out of an ensemble of 10^{11} spins.

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Y. Kubo, I. Diniz, C. Grezes, T. Umeda, J. Isoya, H. Sumiya, T. Yamamoto, H. Abe, S. Onoda, T. Ohshima, V. Jacques, A. Dréau, J. -F. Roch, A. Auffeves, D. Vion, D. Esteve, P. Bertet. 2012-05-25. Electron spin resonance detected by a superconducting qubit. https://doi.org/10.1103/physrevb.86.064514

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