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arXiv · 1708.09287

Inductive-detection electron-spin resonance spectroscopy with $\mathbf{65}\,$spins$/\sqrt{\text{Hz}}$ sensitivity

S. Probst·A. Bienfait·P. Campagne-Ibarcq·J. J. Pla·B. Albanese·J. F. Da Silva Barbosa·T. Schenkel·D. Vion·D. Esteve·K. Mølmer·J. J. L. Morton·R. Heeres·P. Bertet
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Abstract

We report electron spin resonance spectroscopy measurements performed at millikelvin temperatures in a custom-built spectrometer comprising a superconducting micro-resonator at $7$ GHz and a Josephson parametric amplifier. Owing to the small ${\sim}10^{-12}\lambda^3$ magnetic resonator mode volume and to the low noise of the parametric amplifier, the spectrometer sensitivity reaches $260\pm40$ spins$/$echo and $65\pm10$ $\mathrm{spins}/\sqrt{\text{Hz}}$, respectively.

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S. Probst, A. Bienfait, P. Campagne-Ibarcq, J. J. Pla, B. Albanese, J. F. Da Silva Barbosa, T. Schenkel, D. Vion, D. Esteve, K. Mølmer, J. J. L. Morton, R. Heeres, P. Bertet. 2017-08-30. Inductive-detection electron-spin resonance spectroscopy with $\mathbf{65}\,$spins$/\sqrt{\text{Hz}}$ sensitivity. https://doi.org/10.1063/1.5002540

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