利用域排列算法设计铌酸锂晶体实现3μm中红外波段频域纯态单光子源  

Preparation of spectrally pure single-photon source at 3μm mid-infrared band from lithium niobate crystal with domain sequence algorithm

作　　者：张晨涛 石小涛 朱文新 朱金龙[1] 郝向英 金锐博[1] Zhang Chen-Tao;Shi Xiao-Tao;Zhu Wen-Xin;Zhu Jin-Long;Hao Xiang-Ying;Jin Rui-Bo(Hubei Key Laboratory of Optical Information and Pattern Recognition,Wuhan Institute of Technology,Wuhan 430205,China)

机构地区：[1]武汉工程大学,光学信息与模式识别湖北省重点实验室,武汉430205

出　　处：《物理学报》2022年第20期75-81,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:12074299,91836102,11704290)资助的课题。

摘　　要：中红外波段的单光子源对于下一代量子传感、量子通信和量子成像的研究非常重要.目前常用的产生中红外单光子源的方法是基于周期极化铌酸锂(periodically poled lithium niobate,PPLN)自发参量下转换过程.但是,基于普通PPLN制备的单光子源频域纯度不高,最高值只有0.82左右,会影响量子信息处理方案的保真度.本文利用域设计理论对30 mm长铌酸锂晶体的4000个域进行了定制化排列,消除了相位匹配函数中的旁瓣,获得了高斯型的分布.计算得到的单光子源的频域纯度可达0.99,可调谐范围为2.7—3.3μm.该定制极化铌酸锂(customized poled lithium niobate,CPLN)有望为中红外波段量子信息研究提供性能优异的单光子光源.The single-photon source in mid-infrared(MIR)band is very important for the next generation of quantum sensing,quantum communication and quantum imaging.At present,the commonly used method of generating MIR single-photon source is based on the spontaneous parametric down conversion(SPDC)process in the periodically poled lithium niobate(PPLN)crystal.However,the spectral purity of single-photon source based on the ordinary PPLN is not high,specifically,its maximum value is only about 0.82,which affects the fidelity of quantum information processing scheme.In this paper,4000 polarized domains in a 30-mm-long LN crystal are customized by using the domain design theory.The sidelobes in the phase matching function are eliminated,and the Gaussian distribution is obtained.The calculated spectral purity of the single-photon source can reach 0.99,and its tunable range is 2.7–3.3μm.The customized poled lithium niobate(CPLN)is expected to provide a single-photon source with excellent performance for the study of quantum information in the MIR band.

关 键 词：铌酸锂晶体 极化周期设计 中红外波段 量子光源 

分 类 号：O76[理学—晶体学] O431.2[机械工程—光学工程]