Generation of broadband polarization-orthogonal photon pairs via the dispersion-engineered thin-film lithium niobate waveguide  

作　　者：Ji-Ning Zhang Tong-Yu Zhang Jia-Chen Duan Yan-Xiao Gong Shi-Ning Zhu 张继宁;张同宇;端家晨;龚彦晓;祝世宁(National Laboratory of Solid State Microstructures,School of Physics,Nanjing University,Nanjing 210093,China)

机构地区：[1]National Laboratory of Solid State Microstructures,School of Physics,Nanjing University,Nanjing 210093,China

出　　处：《Chinese Physics B》2024年第11期46-51,共6页中国物理B（英文版）

基　　金：Project supported by the National Key Research and Development Program of China(Grant No.2019YFA0705000);Innovation Program for Quantum Science and Technology(Grant No.2021ZD0301500);Leading-edge Technology Program of Jiangsu Natural Science Foundation(Grant No.BK20192001);the National Natural Science Foundation of China(Grant Nos.51890861 and 11974178).

摘　　要：Broadband photon pairs are highly desirable for quantum metrology,quantum sensing,and quantum communication.Such sources are usually designed through type-0 phase-matching spontaneous parametric down-conversion(SPDC)that makes the photon pairs hard to separate in the frequency-degenerate case and thus limits their applications.In this paper,we design a broadband frequency-degenerate telecom-band photon pair source via the type-II SPDC in a dispersion-engineered thin-film lithium niobate waveguide,where the polarization modes of photon pairs are orthogonal and thus are easily separated deterministically.With a 5-mm-long waveguide,our design can achieve a bandwidth of 5.56 THz(44.8 nm),which is 8.6 times larger than that of the bulk lithium niobate,and the central wavelength can be flexibly adjusted.Our design is a promising approach towards high-quality integrated photon sources and may have wide applications in photonic quantum technologies.

关 键 词：broadband photon pair source spontaneous parametric down-conversion dispersion engineering thin-film lithium niobate waveguide 

分 类 号：O43[机械工程—光学工程]