English

Off-resonant emission of photon pairs in nonlinear optical cavities

Quantum Physics 2018-05-23 v1

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.

Keywords

Cite

@article{arxiv.1805.08467,
  title  = {Off-resonant emission of photon pairs in nonlinear optical cavities},
  author = {Valentin A. Averchenko and Gerhard Schunk and Michael Förtsch and Martin Fischer and Dmitry V. Strekalov and Gerd Leuchs and Christoph Marquardt},
  journal= {arXiv preprint arXiv:1805.08467},
  year   = {2018}
}