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arXiv · 1408.0659

Lamb-Dicke spectroscopy of atoms in a hollow-core photonic crystal fibre

Shoichi Okaba·Tetsushi Takano·Fetah Benabid·Tom Bradley·Luca Vincetti·Zakhar Maizelis·Valery Yampol'skii·Franco Nori·Hidetoshi Katori
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Abstract

Unlike photons, which are conveniently handled by mirrors and optical fibres without loss of coherence, atoms lose their coherence via atom-atom and atom-wall interactions. This decoherence of atoms deteriorates the performance of atomic clocks and magnetometers, and also hinders their miniaturisation. Here we report a novel platform for precision spectroscopy. Ultracold strontium atoms inside a kKagome-lattice hollow-core photonic crystal fibre (HC-PCF) are transversely confined by an optical lattice to prevent atoms from interacting with the fibre wall. By confining at most one atom in each lattice site, to avoid atom-atom interactions and Doppler effect, a 7.8-kHz-wide spectrum is observed for the $^1 S_0-{}^3P_1$ (m=0) transition. Atoms singly trapped in a magic lattice in hollow-core photonic crystal fibresHC-PCFs improve the optical depth while preserving atomic coherence time.

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Shoichi Okaba, Tetsushi Takano, Fetah Benabid, Tom Bradley, Luca Vincetti, Zakhar Maizelis, Valery Yampol'skii, Franco Nori, Hidetoshi Katori. 2014-08-04. Lamb-Dicke spectroscopy of atoms in a hollow-core photonic crystal fibre. https://doi.org/10.1038/ncomms5096

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