Physical Review Letters

Millisecond Photon Lifetime in a Slow-Light Microcavity

Vincent Huet, Alphonse Rasoloniaina, Pierre Guillemé, Philippe Rochard, Patrice Féron, Michel Mortier, Ariel Levenson, Kamel Bencheikh, Alejandro M. Yacomotti, Yannick Dumeige

Published Mar 29, 2016• 98 citations

Publisher

Abstract

Optical microcavities with ultralong photon storage times are of central importance for integrated nanophotonics. To date, record quality (Q) factors up to 10^{11} have been measured in millimetric-size single-crystal whispering-gallery-mode (WGM) resonators, and 10^{10} in silica or glass microresonators. We show that, by introducing slow-light effects in an active WGM microresonator, it is possible to enhance the photon lifetime by several orders of magnitude, thus circumventing both fabrication imperfections and residual absorption. The slow-light effect is obtained from coherent population oscillations in an erbium-doped fluoride glass microsphere, producing strong dispersion of the WGM (group index n_{g}∼10^{6}). As a result, a photon lifetime up to 2.5 ms at room temperature has been measured, corresponding to a Q factor of 3×10^{12} at 1530 nm. This system could yield a new type of optical memory microarray with ultralong storage times.

DOI: 10.1103/physrevlett.116.133902

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