时域多模飞秒压缩光场测量中的本地光脉冲整形研究

Pulse Shaping of Local Beam in the Measurement of Temporal Multimode Femtosecond Squeezed Light

基于飞秒脉冲的同步泵浦参量过程产生的多模时域飞秒压缩光场,由于其独特的优势,特别是可以享有单模光纤网络兼容,是实现可扩展量子计算及大容量量子通讯的良好光源。由于无法实现多模时域飞秒压缩光场的空间分离,目前对于多模时域飞秒压缩光场的测量,采用最为有效的平衡零拍探测。因此如何构造与时域飞秒压缩光场时域函数分布相同的本地光,是其中的关键内容,并直接影响测量效果。本文主要理论研究了本地脉冲光的时域整形方案,分析了系统参数对整形后的多模本地光的保真度以及系统调制效率的影响,并结合实验参数提出可能的解决办法。

Temporal multimode femtosecond pulse squeezed light field generated from synchronous pump optical parametric oscillator （SPOPO） based on femtosecond pulse, for its unique advantages, in particular, the natural compatibility with existing single-mode fiber networks, is a great light source for scalable quantum computation and large--capacity quantum communication. At present, the most effective detection scheme is the balanced homodyne detection （BHD） , due to the inability to realize the spatial separation of the multimode temporal femtosecond squeezed light field. Therefore, how to construct the local light which has the same temporal distribution function with the temporal femtosecond squeezed light field is the key question, and it directly affects the measurement efficiency. In this paper, we study the temporal shaping scheme of local pulsed light, analyze the influences of several parameters on the purification of the output multimode local light and the efficiency of modulation, and propose some possible solutions considering the experimental parameters.