基于四波混频过程产生介于锥形探针光和锥形共轭光之间的多模量子关联

Experimental generation of multimode quantum correlations between a conical probe and a conical conjugate based on a four-wave mixing process

多模量子关联与纠缠在基础科学研究以及量子信息处理、量子通信等领域有着重要作用.本文基于热铷原子系综中的四波混频过程,通过构建具有空间结构的锥形泵浦光和锥形探针光,在实验上产生具有量子关联的锥形探针光和锥形共轭光,并测量到量子关联光束之间的强度差压缩约–2.6dB.通过改变单光子失谐、双光子失谐、泵浦光功率和铷原子池温度等实验参数,研究量子关联光束之间的强度差噪声随实验参数的变化关系.除此之外,通过“整体衰减法”和“局部切割法”对量子关联光束进行不同方式的处理,不仅实验测量了量子关联随透射率的变化关系,而且深入研究了量子关联的多模特性.本文的实验结果在量子信息处理以及量子通信领域有着潜在的应用价值.

Multimode quantum correlations and entanglements has drawn much attention recently due to its importance for both fundamental science and the future development of quantum information processing and quantum communication.Here,by using a four-wave mixing process with a conical pump beam and a conical probe beam,we experimentally generate the multimode quantum correlations between a conical probe beam and a conical conjugate beam,and we also observe about-2.6-dB intensity-difference squeezing between these two conical beams.In addition,we find the optimal value of each parameter in this scheme for further applications.Besides,the multi-spatial-mode nature of the generated quantum correlated beams is shown by comparing the variation tendencies of the intensity-difference noise of the probe and conjugate beams under global attenuation and local cutting attenuation.Our scheme may find potential applications in quantum information processing and quantum communication.