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arXiv · 1407.5064

Coupling of a locally implanted rare-earth ion ensemble to a superconducting micro-resonator

Abstract

We demonstrate the coupling of rare-earth ions locally implanted in a substrate (Gd$^{3+}$ in Al$_{2}$O$_{3}$) to a superconducting NbN lumped-element micro-resonator. The hybrid device is fabricated by a controlled ion implantation of rare-earth ions in well-defined micron-sized areas, aligned to lithographically defined micro-resonators. The technique does not degrade the internal quality factor of the resonators which remain above $10^{5}$. Using microwave absorption spectroscopy we observe electron-spin resonances in good agreement with numerical modelling and extract corresponding coupling rates of the order of $1$ MHz and spin linewidths of $50 - 65$ MHz.

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I. Wisby, S. E. de Graaf, R. Gwilliam, A. Adamyan, S. Kubatkin, P. J. Meeson, A. Ya. Tzalenchuk, T. Lindström. 2014-09-10. Coupling of a locally implanted rare-earth ion ensemble to a superconducting micro-resonator. https://doi.org/10.1063/1.4894455

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