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arXiv · 2001.01084

Nanofiber-based high-Q microresonator for cryogenic applications

Johanna Hütner·Thomas Hoinkes·Martin Becker·Manfred Rothhardt·Arno Rauschenbeutel·Sarah M. Skoff
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Abstract

We demonstrate a cryo-compatible, fully fiber-integrated, alignment-free optical microresonator. The compatibility with low temperatures expands its possible applications to the wide field of solid-state quantum optics, where a cryogenic environment is often a requirement. At a temperature of 4.6 K we obtain a quality factor of $\mathbf{(9.9 \pm 0.7) \times 10^6}$. In conjunction with the small mode volume provided by the nanofiber, this cavity can be either used in the coherent dynamics or the fast cavity regime, where it can provide a Purcell factor of up to 15. Our resonator is therefore suitable for significantly enhancing the coupling between light and a large variety of different quantum emitters and due to its proven performance over a wide temperature range, also lends itself for the implementation of quantum hybrid systems.

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Johanna Hütner, Thomas Hoinkes, Martin Becker, Manfred Rothhardt, Arno Rauschenbeutel, Sarah M. Skoff. 2020-01-04. Nanofiber-based high-Q microresonator for cryogenic applications. https://doi.org/10.1364/oe.381286

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