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arXiv · 1703.07621

Optical coherence of $^{166}$Er:$^{7}$LiYF$_4$ crystal below 1 Kelvin

Nadezhda Kukharchyk·Dmitriy Sholokhov·Stella L. Korableva·Alexey A. Kalachev·Pavel A. Bushev
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Abstract

We explore spin dynamics of isotopically purified $^{166}$Er:$^{7}$LiYF$_4$ crystal below 1 Kelvin and at weak magnetic fields $<$0.3 T. Crystals grown in our lab demonstrate record-narrow inhomogeneous optical broadening down to 16~MHz. Solid state atomic ensembles with such narrow linewidths are very attractive for the implementation of off-resonant Raman quantum memory and for the interfacing of superconducting quantum circuits and telecom C-band optical photons. Both applications require low magnetic field of $\sim10$ mT. However, at conventional experimental temperatures $T>1.5$ K and time scales of $μ$s, spin coherence of Er:LYF crystal appears only at magnetic fields above 1 Tesla. In the present work, we demonstrate spin coherence of Er:LYF crystals at the field range compatible with ZEFOZ transitions of $^{167}$Er isotope and with working conditions of superconducting quantum circuits.

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Nadezhda Kukharchyk, Dmitriy Sholokhov, Stella L. Korableva, Alexey A. Kalachev, Pavel A. Bushev. 2017-11-10. Optical coherence of $^{166}$Er:$^{7}$LiYF$_4$ crystal below 1 Kelvin. https://doi.org/10.1088/1367-2630%2Faaa7e4

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