Monolayer-Based Single-Photon Source in a Liquid-Helium-Free Open Cavity Featuring 65% Brightness and Quantum Coherence
Jens-Christian Drawer, Victor N. Mitryakhin, Hangyong Shan, Sven Stephan, Moritz Gittinger, Lukas Lackner, Bo Han, Gilbert Leibeling, Falk Eilenberger, Rounak Banerjee, Sefaattin Tongay, Kenji Watanabe, Takashi Taniguchi, Christoph Lienau, Martin Silies, C. Antón, Martin Esmann, Christian Schneider
Abstract
High Resolution Image Download MS PowerPoint Slide Solid-state single-photon sources are central building blocks in quantum information processing. Atomically thin crystals have emerged as sources of nonclassical light; however, they perform below the state-of-the-art devices based on volume crystals. Here, we implement a bright single-photon source based on an atomically thin sheet of WSe 2 coupled to a tunable optical cavity in a liquid-helium-free cryostat without the further need for active stabilization. Its performance is characterized by high single-photon purity (g (2) (0) = 4.7 ± 0.7%) and record-high, first-lens brightness of linearly polarized photons of 65 ± 4%, representing a decisive step toward real-world quantum applications. The high performance of our devices allows us to observe two-photon interference in a Hong–Ou–Mandel experiment with 2% visibility limited by the emitter coherence time and setup resolution. Our results thus demonstrate that the combination of the unique properties of two-dimensional materials and versatile open cavities emerges as an inspiring avenue for novel quantum optoelectronic devices.