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arXiv:2108.08738 · Revista Mexicana de Física

An experimental setup to generate narrowband bi-photons via four-wave mixing in cold atoms

N. Arias-Téllez, I. F. Ángeles-Aguillón, D. Martínez-Cara, A. Martínez-Vallejo, L. Y. Villegas Aguilar, L. A. Mendoza-López, Y. M. Torres, R. A. Gutiérrez-Arenas, Rocío Jáuregui, I. Pérez-Castillo, Alessandro Ceré, Daniel Sahagún

Published Apr 5, 2022• 3 citations

Abstract

We present our recently-built experimental setup designed to generate near-infrared and narrow-band correlated photon pairs by inducingfour-wave mixing in a cold gas of 87Rb atoms confined in a magneto-optical trap. The experimental setup and its automation and control approach are described in detail. A characterization of the optical density of the atomic ensemble as well as the basic statistical measurements of the generated light are reported. The non-classical nature of the photons pairs is confirmed by observing a violation of Cauchy-Schwarz inequality by a factor of 5.6 × 10 5 in a Hanbury Brown – Twiss interferometer. A 1/e coherence time for the heralded, idler photons of 4.4 ± 0.1 ns is estimated from our observations. We are able to achieve a value of 104 s−1pair-detection-rate, which results in a spectral brightness of 280 (MHz s)−1. The combination of high brightness and narrow-band spectrum makes this photon-pair source a viable tool in fundamental studies of quantum states and opens the door to use them in quantum technologies.

DOI: 10.31349/revmexfis.68.031303

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