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arXiv · 2001.04854

Hyperfine spectroscopy in a quantum-limited spectrometer

S. Probst·G. L. Zhang·M. Rančić·V. Ranjan·M. Le Dantec·Z. Zhong·B. Albanese·A. Doll·R. B. Liu·J. J. L. Morton·T. Chanelière·P. Goldner·D. Vion·D. Esteve·P. Bertet
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Abstract

We report measurements of electron spin echo envelope modulation (ESEEM) performed at millikelvin temperatures in a custom-built high-sensitivity spectrometer based on superconducting micro-resonators. The high quality factor and small mode volume (down to 0.2pL) of the resonator allow to probe a small number of spins, down to $5\cdot 10^2$. We measure 2-pulse ESEEM on two systems: erbium ions coupled to $^{183}$W nuclei in a natural-abundance $\text{CaWO}_4$ crystal, and bismuth donors coupled to residual $^{29}$Si nuclei in a silicon substrate that was isotopically enriched in the $^{28}$Si isotope. We also measure 3- and 5-pulse ESEEM for the bismuth donors in silicon. Quantitative agreement is obtained for both the hyperfine coupling strength of proximal nuclei, and the nuclear spin concentration.

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S. Probst, G. L. Zhang, M. Rančić, V. Ranjan, M. Le Dantec, Z. Zhong, B. Albanese, A. Doll, R. B. Liu, J. J. L. Morton, T. Chanelière, P. Goldner, D. Vion, D. Esteve, P. Bertet. 2020-01-14. Hyperfine spectroscopy in a quantum-limited spectrometer. https://doi.org/10.5194/mr-1-315-2020

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