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arXiv · 2103.05619

Open-cavity in closed-cycle cryostat as a quantum optics platform

Samarth Vadia·Johannes Scherzer·Holger Thierschmann·Clemens Schäfermeier·Claudio Dal Savio·Takashi Taniguchi·Kenji Watanabe·David Hunger·Khaled Karraï·Alexander Högele
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Abstract

The introduction of an optical resonator can enable efficient and precise interaction between a photon and a solid-state emitter. It facilitates the study of strong light-matter interaction, polaritonic physics and presents a powerful interface for quantum communication and computing. A pivotal aspect in the progress of light-matter interaction with solid-state systems is the challenge of combining the requirements of cryogenic temperature and high mechanical stability against vibrations while maintaining sufficient degrees of freedom for in-situ tunability. Here, we present a fiber-based open Fabry-P\'{e}rot cavity in a closed-cycle cryostat exhibiting ultra-high mechanical stability while providing wide-range tunability in all three spatial directions. We characterize the setup and demonstrate the operation with the root-mean-square cavity length fluctuation of less than $90$ pm at temperature of $6.5$ K and integration bandwidth of $100$ kHz. Finally, we benchmark the cavity performance by demonstrating the strong-coupling formation of exciton-polaritons in monolayer WSe$_2$ with a cooperativity of $1.6$. This set of results manifests the open-cavity in a closed-cycle cryostat as a versatile and powerful platform for low-temperature cavity QED experiments.

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quant-phcond-mat.mes-hallphysics.ins-detphysics.optics

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Samarth Vadia, Johannes Scherzer, Holger Thierschmann, Clemens Schäfermeier, Claudio Dal Savio, Takashi Taniguchi, Kenji Watanabe, David Hunger, Khaled Karraï, Alexander Högele. 2021-03-09. Open-cavity in closed-cycle cryostat as a quantum optics platform. https://doi.org/10.1103/prxquantum.2.040318

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