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arXiv · 2102.13113

Gigahertz-Bandwidth Optical Memory in Pr$^{3+}$:Y$_2$SiO$_5$

M. Nicolle·J. N. Becker·C. Weinzetl·I. A. Walmsley·P. M. Ledingham
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Abstract

We experimentally study a broadband implementation of the atomic frequency comb (AFC) rephasing protocol with a cryogenically cooled Pr$^{3+}$:Y$_2$SiO$_5$ crystal. To allow for storage of broadband pulses, we explore a novel regime where the input photonic bandwidth closely matches the inhomogeneous broadening of the material $(\sim5\,\textrm{GHz})$, thereby significantly exceeding the hyperfine ground and excited state splitting $(\sim10\,\textrm{MHz})$. Through an investigation of different AFC preparation parameters, we measure a maximum efficiency of $10\%$ after a rephasing time of $12.5\,$ns. With a suboptimal AFC, we witness up to 12 rephased temporal modes.

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M. Nicolle, J. N. Becker, C. Weinzetl, I. A. Walmsley, P. M. Ledingham. 2021-02-25. Gigahertz-Bandwidth Optical Memory in Pr$^{3+}$:Y$_2$SiO$_5$. https://doi.org/10.1364/ol.423642

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