Towards spontaneous parametric down-conversion at low temperatures
Kazan E. K. Zavoisky Physical-Technical Institute, 10/7 Sibirsky trakt Str., Kazan, 420029 Russia
2 Institute of Spectroscopy RAS Moscow, 5 Fizicheskaya Str., Troitsk, Moscow 108840 Russia
3 Lomonosov Moscow State University, GSP-1 Leninskie Gory, Moscow, 119991 Russia
* Corresponding author: firstname.lastname@example.org
Published online: 31 October 2017
The possibility of observing spontaneous parametric down-conversion in doped nonlinear crystals at low temperatures, which would be useful for combining heralded single-photon sources and quantum memories, is studied theoretically. The ordinary refractive index of a lithium niobate crystal doped with magnesium oxide LiNbO3:MgO is measured at liquid nitrogen and helium temperatures. On the basis of the experimental data, the coefficients of the Sellmeier equation are determined for the temperatures from 5 to 300 K. In addition, a poling period of the nonlinear crystal has been calculated for observing type-0 spontaneous parametric down-conversion (ooo-synchronism) at the liquid helium temperature under pumping at the wavelength of λp = 532 nm and emission of the signal field at the wavelength of λs = 794 nm, which corresponds to the resonant absorption line of Tm3+ doped ions.
© The Authors, published by EDP Sciences, 2017
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