利用楔角KTP晶体实现低阈值非简并光学参量放大器的运转  

Realization of Low Threshold Operation of Non-Degenerate Optical Parameteric Amplifier with Wedged KTP Crystal

作　　者：张敏[1] 周瑶瑶[1] 李芳[1] 贾晓军[1] 

机构地区：[1]山西大学光电研究所量子光学与光量子器件国家重点实验室,山西太原030006

出　　处：《光学学报》2014年第3期270-274,共5页Acta Optica Sinica

基　　金：国家973计划(2010CB923103);国家自然科学基金创新研究群体科学基金(61121064);国家自然科学基金(11322440;11074157)

摘　　要：非简并光学参量放大器产生的纠缠态光场是连续变量量子信息科学研究的重要资源。随着量子网络及量子计算的发展,需要更多组份纠缠态光场来完成对更复杂的量子信息的研究。一般的多组份纠缠态光场是将多个压缩态光场或者Einstein-Podolsky-Rosen(EPR)纠缠态光场通过不同的分束器阵列耦合而成,需要同时制备多个经典相干的EPR纠缠态光场。采用带楔角的非线性晶体,使非简并光学参量放大器的振荡阈值从原来的250mW降低至45mW,当注入腔内抽运光功率为23mW时,依然可以得到正交振幅及相位分量关联噪声分别低于量子噪声极限5.5dB的EPR纠缠态光场。在此基础上,可以使用一台激光器同时抽运多个非简并光学参量放大器来获得所希望的多组份纠缠态光场。Entangled optical field generated by a non-degenerate optical parametric amplifier （NOPA）, has been considered as an important resource of continuous variable quantum information research. With the development of quantum networks and quantum computation, multi-partite entangled states with more sub-modes are required to complete more complex research of quantum information. Generally, Multi-partite entangled states can be obtained by means of coupling several Enstein-Podolsky-Rosen （EPR） entangled states or squeezed states with classical coherence through different beam splitters. The threshold of the NOPA is reduced from 250 mW to 45 mW by using a wedged nonlinear crystal. When pumping power is 23 mW, the correlation noises of quadrature amplitude and quadrature phase of the EPR entangled optical fields are 5.5 dB below the corresponding quantum noise limits. Thus we can pump much more NOPAs with only one laser source and obtain the multi-partite entangled states as needed.

关 键 词：量子光学 Einstein-Podolsky-Rosen纠缠态光场 楔角非线性晶体 阈值 关联噪声 

分 类 号：O431.2[机械工程—光学工程]