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arXiv · 1710.10801

Electron Paramagnetic Resonance Spectroscopy of Er$^{3+}$:Y$_2$SiO$_5$ Using Josephson Bifurcation Amplifier: Observation of Hyperfine and Quadrupole Structures

Rangga P. Budoyo·Kosuke Kakuyanagi·Hiraku Toida·Yuichiro Matsuzaki·William J. Munro·Hiroshi Yamaguchi·Shiro Saito
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Abstract

We performed magnetic field and frequency tunable electron paramagnetic resonance spectroscopy of an Er$^{3+}$ doped Y$_2$SiO$_5$ crystal by observing the change in flux induced on a direct current-superconducting quantum interference device (dc-SQUID) loop of a tunable Josephson bifurcation amplifer. The observed spectra show multiple transitions which agree well with the simulated energy levels, taking into account the hyperfine and quadrupole interactions of $^{167}$Er. The sensing volume is about 0.15 pl, and our inferred measurement sensitivity (limited by external flux noise) is approximately $1.5\times10^4$ electron spins for a 1 s measurement. The sensitivity value is two orders of magnitude better than similar schemes using dc-SQUID switching readout.

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Rangga P. Budoyo, Kosuke Kakuyanagi, Hiraku Toida, Yuichiro Matsuzaki, William J. Munro, Hiroshi Yamaguchi, Shiro Saito. 2017-10-30. Electron Paramagnetic Resonance Spectroscopy of Er$^{3+}$:Y$_2$SiO$_5$ Using Josephson Bifurcation Amplifier: Observation of Hyperfine and Quadrupole Structures. https://doi.org/10.1103/physrevmaterials.2.011403

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