Design of spontaneous parametric down-conversion in integrated hybrid SixNy-PPLN waveguides

TL;DR

This paper presents a novel hybrid SixNy-PPLN waveguide design for efficient, high-purity photon pair generation suitable for quantum information processing, with high conversion efficiency and spectral purity.

Contribution

The paper introduces a chip-scale hybrid waveguide design that achieves high second harmonic generation efficiency and intrinsic purity for SPDC photons in the telecommunication band.

Findings

Second harmonic generation efficiency of 225% W^(-1)*cm^(-2) at 1560nm.

Intrinsic purity of SPDC photons up to 95.17%.

Generation rate of 2.87 x 10^7 pairs/s/mW within the SPDC bandwidth.

Abstract

High-efficient and high-purity photon sources are highly desired for quantum information processing. We report the design of a chip-scale hybrid SixNy and thin film periodically-poled lithium niobate waveguide for generating high-purity type-II spontaneous parametric down conversion (SPDC) photons in telecommunication band. The modeled second harmonic generation efficiency of 225% W^(-1)*cm^(-2) is obtained at 1560nm. Joint spectral analysis is performed to estimate the frequency correlation of SPDC photons, yielding intrinsic purity with up to 95.17%. The generation rate of these high-purity photon pairs is estimated to be 2.87 * 10^7 pairs/s/mW within the bandwidth of SPDC. Our chip-scale hybrid waveguide design has the potential for large scale on-chip quantum information processing and integrated photon-efficient quantum key distribution through high-dimensional time-energy encoding.