Open-Cavity in Closed-Cycle Cryostat as a Quantum Optics Platform
Samarth Vadia, Karrai, Holger Thierschmann, Clemens Schäfermeier, Claudio Dal Savio, Scherzer, Högele, Taniguchi, Watanabe, Hunger
Abstract
The introduction of an optical resonator can enable efficient and precise interaction between a photon\nand a solid-state emitter. It facilitates the study of strong light-matter interaction, polaritonic physics and\npresents a powerful interface for quantum communication and computing. A pivotal aspect in the progress\nof light-matter interaction with solid-state systems is the challenge of combining the requirements of cryo-\ngenic temperature and high mechanical stability against vibrations while maintaining sufficient degrees of\nfreedom for in situ tunability. Here, we present a fiber-based open Fabry-Pérot cavity in a closed-cycle\ncryostat exhibiting ultrahigh mechanical stability while providing wide-range tunability in all three spatial\ndirections. We characterize the setup and demonstrate the operation with the root-mean-square cavity-\nlength fluctuation of less than 90 pm at temperature of 6.5 K and integration bandwidth of 100 kHz.\nFinally, we benchmark the cavity performance by demonstrating the strong-coupling formation of exciton\npolaritons in monolayer WSe2 with a cooperativity of 1.6. This set of results manifests the open cavity in\na closed-cycle cryostat as a versatile and powerful platform for low-temperature cavity QED experiments.