Off-resonant emission of photon pairs in nonlinear optical cavities

Valentin A. Averchenko; Gerhard Schunk; Michael Förtsch; Martin Fischer; Dmitry V. Strekalov; Gerd Leuchs; Christoph Marquardt

arXiv · 1805.08467

Off-resonant emission of photon pairs in nonlinear optical cavities

Valentin A. Averchenko·Gerhard Schunk·Michael Förtsch·Martin Fischer·Dmitry V. Strekalov·Gerd Leuchs·Christoph Marquardt

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Abstract

Cavity-assisted spontaneous parametric down-conversion (SPDC) and spontaneous four-wave mixing (SFWM) in nonlinear optical materials are practical and versatile methods to generate narrowband time-energy entangled photon pairs. Time-energy entangled photons with tailored spectro-temporal properties are particularly useful for efficient quantum optical interfaces. In this work we study the generation of photon pairs in cavity-assisted SPDC and SFWM for the general case of off-resonant conversion, namely, when the frequencies of the generated photons do not match the cavity resonances. Such a frequency mismatch in particular depends on temperature and requires an additional control in the experiment. First, we propose a generic model, for description of cavity-assisted SPDC and SFWM. We show that in both processes the mismatch reduces the generation rate of photons, distorts the spectrum and the auto-correlation function of the generated fields, as well as affects the photon generation dynamics. Second, we verify the results experimentally using parametric generation of photon pairs in a nonlinear whispering gallery mode resonator (WGMR) as an experimental platform with controlled frequency mismatch. Our work reveals the role of the frequency mismatch in the photon generation process and shows a way to control it. Obtained results constitute one more step in the direction of full control over the spectro-temporal properties of entangled photon pairs and the heralded generation of single-photon pulses with a tailored temporal mode.

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Valentin A. Averchenko, Gerhard Schunk, Michael Förtsch, Martin Fischer, Dmitry V. Strekalov, Gerd Leuchs, Christoph Marquardt. 2018-05-22. Off-resonant emission of photon pairs in nonlinear optical cavities. https://arxiv.org/abs/1805.08467

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