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Towards an Alignment-Free, Impedance-Matched Cavity Quantum Memory in a Thulium-Doped Crystal

Antariksha Das, Jacob H. Davidson, Tanmoy Chakraborty, Anna L. Tchebotareva, Wolfgang Tittel

Published Jan 1, 2023• 1 citation
Publisher

Abstract

Here, we discuss our experimental efforts toward building an alignment-free, long-lived, and efficient cavity-enhanced quantum memory in a thulium-doped crystal. A significant step forward for creating efficient quantum memories with long optical storage times.
DOI
10.1364/cleo_si.2023.sth5c.6

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Cavity assisted quantum memory storage has been proposed [PRA 82, 022310 (2010), PRA 82, 022311 (2010)] for creating efficient (close to unity) quantum memories using weakly absorbing materials. Using this approach we experimentally demonstrate a significant (about 20-fold) enhancement in quantum memory efficiency compared to the no cavity case. A strong dispersion originating from absorption engineering inside the cavity was observed, which directly affect the cavity line-width. A more than 3 orders of magnitude reduction of cavity mode spacing and cavity line-width from GHz to MHz was observed. We are not aware of any previous observation of several orders of magnitudes cavity mode spacing and cavity line-width reduction due to slow light effects.