压缩真空态光场在光纤中传输特性的研究  

Investigation on the Transmission Characteristic of Squeezed Vacuum State over Optical Fibers

作　　者：张超[1,2] 冯晋霞 李渊骥[1,2] 张宽收 ZHANG Chao;FENG Jin-xia;LI Yuan-ji;ZHANG Kuan-shou(State Key of Laboratory of Quantum Optics and Quantum Optics Devices,Institute of Opto-Electronics,Shanxi University,Taiyuan 030006,China;Collaborative Innovation Center of Extreme Optics,Shanxi University,Taiyuan 030006,China)

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 [2]山西大学极端光学协同创新中心,山西太原030006

出　　处：《量子光学学报》2021年第1期8-14,共7页Journal of Quantum Optics

基　　金：国家重点研发计划项目(2016YFA0301401)。

摘　　要：本文利用简并光学参量振荡器实验制备了光通信波段1.5μm压缩真空态光场,压缩度为(5.03±0.13) d B。将已制备的1.5μm压缩真空态光场和同频率本地振荡光采用偏振复用的方式耦合注入单模光纤中进行传输,在理论和实验上研究了压缩真空态光场在光纤信道传输过程中经典和量子特性的演化,并讨论了本地振荡光在光纤信道中引起的声导波布里渊散射对传输过程的压缩真空态光场影响。实验测量了1.5μm压缩真空态光场在单模光纤中传输距离为8 km时,压缩度为0.14 dB,压缩特性仍得到保持。该研究为实现基于光纤的城域量子信息网络等奠定基础。Squeezed states at the fiber telecommunication wavelength is an essential quantum resource for the practical applications based on optical fiber. The squeezed light at 1.5 μm can be utilized to realize quantum precision measurement,as laser interferometer for gravitational wave detection. In spite of the fact that the optical power attenuation of light in a standard telecommunication fiber is the lowest at a wavelength of 1.5 μm, the squeezed states can interact with fiber channels and the decoherence does occur. It is one of the important factors restricting the development of long-distance quantum information. As an ideal quantum channel, optical fiber is the focus of continuous variable quantum information research. In this paper, a squeezed vacuum state at 1.5 μm telecommunication band was obtained using a type-I periodically poled KTP crystal inside a degenerate optical parametric oscillator. In the experiment, the cavity length of DOPO was locked by the pump light, and the squeezed angle of the 1 550 nm squeezed vacuum state light field and the relative phase between the local oscillator light and the squeezed vacuum state light field were locked by coherent control technology. The degree of the generated squeezed vacuum state was(5.03 ± 0.13) d B. The dependence of squeezing factor of squeezed vacuum states on the transmission length of single mode fiber and local oscillator light power was simulated theoretically. The generated squeezed vacuum state and local oscillator light of the identical frequency was coupled into the single-mode optical fiber by polarization multiplexing. Squeezing degree of squeezing vacuum states versus transmission length of single mode fibers were measured experimentally. The influence on transmitted squeezed vacuum state by depolarized guided acoustic wave Brillouin scattering caused by local oscillation light in optical fiber channel is discussed. The measured degree of 0.14 dB of the squeezed vacuum state could still be observed when transmitting through a 8 km single-mod

关 键 词：压缩真空态光场 光学参量振荡器 光纤信道 

分 类 号：O431[机械工程—光学工程]