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Журнал Экспериментальной и Теоретической Физики

SPONTANNOE PARAMETRIChESKOE RASSEYaNIE V DVUOSNYKh NELINEYNO-OPTIChESKIKh KRISTALLAKh: OSOBENNOSTI SOSTOYaNIYa POLYaRIZATsII IZLUChENIYa

Dmitry N. Frolovtsev, Sergey A Magnitskiy

Published Jan 15, 2024• 0 citations

Abstract

A consistent analysis of the quantum state of polarization of SPDC radiation is presented and the peculiarities of the quantum state of polarization of SPDC in biaxial nonlinear optical crystals are considered. It is shown that the SPDC polarization deviation angle can exceed 15°, and the angle between the signal and idler wave vectors D can exceed 30°. Estimates of the curvature of the cone formed by SPDC radiation in biaxial crystals are also given. The influence of SPDC polarization deviation in a non-collinear mode on the entanglement of biphoton states generated by a double-crystal scheme is analyzed, it is shown that Tangle of the generated quantum state can deteriorate by 6%, and conditions are identified under which entanglement can be completely restored.

DOI: 10.31857/s0044451024010048

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