Broadband single-photon-level memory in a hollow-core photonic crystal fibre

• Published in: Nature photonics Vol. 8; no. 4; pp. 287 - 291
• Main Authors: Sprague, M R, Michelberger, P S, Champion, TFM, England, D G, Nunn, J, Jin, X-M, Kolthammer, W S, Abdolvand, A, Russell, PStJ, Walmsley, IA
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group 01.04.2014
• Subjects: Broadband; Fibre; Networks; Optical memory (data storage); Photonic crystals; Photonics; Proposals; Stores
• ISSN: 1749-4885; 1749-4893
• DOI: 10.1038/nphoton.2014.45

Storing information encoded in light is critical for realizing optical buffers for all-optical signal processing and quantum memories for quantum information processing. These proposals require efficient interaction between atoms and a well-defined optical mode. Photonic crystal fibres can enhance light-matter interactions and have engendered a broad range of nonlinear effects; however, the storage of light has proven elusive. Here, we report the first demonstration of an optical memory in a hollow-core photonic crystal fibre. We store gigahertz-bandwidth light in the hyperfine coherence of caesium atoms at room temperature using a far-detuned Raman interaction. We demonstrate a signal-to-noise ratio of 2.6:1 at the single-photon level and a memory efficiency of 27 plus or minus 1%. Our results demonstrate the potential of a room-temperature fibre-integrated optical memory for implementing local nodes of quantum information networks.