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arXiv · 2106.14974

Twenty-three millisecond electron spin coherence of erbium ions in a natural-abundance crystal

Marianne Le Dantec·Miloš Rančić·Sen Lin·Eric Billaud·Vishal Ranjan·Daniel Flanigan·Sylvain Bertaina·Thierry Chanelière·Philippe Goldner·Andreas Erb·Ren Bao Liu·Daniel Estève·Denis Vion·Emmanuel Flurin·Patrice Bertet
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Abstract

Erbium ions doped into crystals have unique properties for quantum information processing, because of their optical transition at 1.5 $\mu$m and of the large magnetic moment of their effective spin-1/2 electronic ground state. Most applications of erbium require however long electron spin coherence times, and this has so far been missing. Here, by selecting a host matrix with a low nuclear-spin density (CaWO$_4$) and by quenching the spectral diffusion due to residual paramagnetic impurities at millikelvin temperatures, we obtain an Er$^{3+}$ electron spin coherence time of 23 ms. This is the longest electron spin coherence time measured in a material with a natural abundance of nuclear spins and on a magnetically-sensitive transition. Our results establish Er$^{3+}$:CaWO$_4$ as a leading platform for quantum networks.

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Marianne Le Dantec, Miloš Rančić, Sen Lin, Eric Billaud, Vishal Ranjan, Daniel Flanigan, Sylvain Bertaina, Thierry Chanelière, Philippe Goldner, Andreas Erb, Ren Bao Liu, Daniel Estève, Denis Vion, Emmanuel Flurin, Patrice Bertet. 2021-06-28. Twenty-three millisecond electron spin coherence of erbium ions in a natural-abundance crystal. https://arxiv.org/abs/2106.14974

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