I摘要热原子系综是一个产生量子光源的高效系统。而高计数率量子光源是研究量子光学和量子通讯的基础。传统且最常用的制备双光子的方法是非线性晶体中二阶非线性效应的参量下转换和硅基材料（如光纤、纳米微环等）中三阶非线性效应的四波混频，这些方法制备的量子光源亮度高，但是相干时间短（亚ps量级）。近年来，原子系统中的自发四波混频得到了广泛研究。自发四波混频在冷原子和热原子系统中都已被实现，这样的光源的相干时间长（ns量级），与原子跃迁谱线线宽自然匹配，可以用于基于原子系统的量子存储。相较于冷原子系统，需要抽真空和搭建磁光阱等复杂光路和控制系统，热原子系统更加简单易行，且易与量子点匹配。本课题将对热原子系统四波混频制备量子光源问题的进行研究。原理上研究如何制备线宽与量子点光源相匹配的窄线宽双光子对。关键词：热原子系统,量子光源,四波混频基本原理,单光子源制备实验系统IIAbstractThehotatomensembleisanefficientsystemforgeneratingquantumlightsources.Thehighcount-ratequantumlightsourceisthebasisofstudyingquantumopticsandquantumcommunication.Thetraditionalandmostcommonlyusedmethodsforpreparingtwophotonsareparametricdown-conversionofsecond-ordernonlineareffectsinnonlinearcrystalsandfour-wavemixingofthird-ordernonlineareffectsinsilicon-basedmaterials(suchasopticalfibersandnanomicrorings,etc.).Thequantumlightsourcespreparedbythesemethodshavehighbrightness,butshortcoherencetime(sub-PSmagnitude).Spontaneousfour-wavemixinginatomicsystemshasbeenstudiedextensivelyinrecentyears.Thespontaneousfour-wavemixinghasbeenrealizedinbothcoldandhotatomicsystems,andsuchalightsourcehasalongcoherencetime(norder),whichnaturallymatchesthelinewidthsoftheatomictransitionlines,andcanbeusedforquantumstorageinatom-basedsystems.Comparedwiththecoldatomsystem,whichrequiresvacuumpumpingandcomplexopticalpathsandcontrolsystemssuchasmagneto-opticaltraps,thehotatomsystemissimplerandeasiertooperate,andcanbeeasilymatchedwiththequantumdots.Inthispaper,thesynthesisofquantumlightsourcebyfour-wavemixinginahotatomicsystemisstudied.Atwo-photonpairwithnarrowlinewidthmatchingthequantumdotlightsourceispreparedtheoretically.Keywords:HotAtomSystem,QuantumLightSource,Four-WaveMixingBasicPrinciple,ExperimentalSystemForPreparationOfSinglePhotonSource1目录摘要.......................................................................IAbstract...................................................................II第一章绪论.................................................................1第二章四波混频的原理及其作用...............................................32.1四波混频的原理.......................................................32.2四波混频的作用.......................................................3第三章制备单光子源的一般方法...............................................53.1基于非线性晶体的自发参量下转换过程的方法.............................53.2基于光纤中自发四波混频过程的方法.....................................7第四章搭建四波混频实验系统.................................................94.1光子对生成的实验装置..................................................94.2实验结果与讨论.......................................................10第五章总结................................................................11本文主要完成以下任务：.....................................................11参考文献...................................................................12致谢.......................................................................142第一章绪论量子通...
