具有正交振幅和相位分量量子关联的纠缠态光场是执行连续变量量子通信和量子计算研究的基本资源。随着量子信息科学的迅速发展，研究和构建可实用的量子信息网络已成为该领域科技工作者的主要目标。为了实现量子信息经由若干量子中继的远距离传送，第一步必须制备与原子存储及光纤通信波段相匹配的多色纠缠态。概述了连续变量纠缠态光场的概念和发展，介绍了产生双色及三色纠缠态光场的实验进展，最后从制备原理和实验方法方面详细描述了近期完成的与原子谱线和光纤传输窗口对应的三色纠缠态光场的研究。

Cluster纠缠态是执行单向量子计算的基本资源。星型Cluster态可用于构建量子信息网络。以非简并光学参变放大器产生的双模压缩态光场为基础，设计了产生连续变量六组份和八组份星型Cluster纠缠态光场的实验方案，并推导了相应的量子不可分判据。计算结果指出，当量子不可分判据中的增益因子取为1时,需要一定的初始压缩度才能制备星型Cluster纠缠态；但当选取最佳增益因子时，极低的压缩也能产生星型纠缠。计算为实验系统设计提供了直接参考。

量子态的光学操控是指在光场的传输、存储和频率变换等过程中用光学方法对光场的量子态进行操作与控制。量子态操控是量子通讯及量子态制备和应用的基础。在简要介绍连续变量多组份纠缠态光场制备的基础上，概述基于多组份纠缠态光场的连续变量量子通讯网络及在执行压缩态和纠缠态光场操控方面的实验研究进展。

Frequency tunable continuous variable (CV) entangled optical beams are experimentally demonstrated from a non-degenerate optical parametric oscillator working above the threshold. The measured correlation variances of amplitude and phase quadratures are 3.2 and 1.5 dB, respectively, below the corresponding shot noise level (SNL) in the tuning range of 580 GHz (2.25 nm). The frequency tuning is realized by simply controlling the temperature of the nonlinear crystal.

利用全固化Nd∶YVO4单频激光器连续输出的1.342 μm激光, 抽运由I类临界相位匹配的LBO晶体构建的谐振倍频腔。当红外抽运光功率为1.14 W时, 获得580 mW单频红光输出, 最大倍频转换效率为50.9%。红光功率稳定性优于±0.5%(1 h), 红外光频率漂移小于±2 MHz(1 min)。

We present a semimonolithic frequency-doubler from 1080 to 540 nm with 80% doubling efficiency and up to 849-mW output power of green light. A frequency-stabilized laser diode (LD) pumped continuous wave (CW) Nd:YAP laser is used as the pump source of the doubler consisting of an α-cut KTP crystal and an input mirror. The frequency stabilities of the output second harmonic wave are better than +/-246 kHz and +/-2.3 MHz in 1 and 30 minutes, respectively, and the intensity fluctuation is less than +/-0.65%.

Using lock-in amplifer and proportional, integral, and derivative (PID) electric circuit, the frequency of diode laser is stabilized on a highly mechanical stable Fabry-Perot (FP) cavity transmission peak. When the frequency locking system is on, the frequency tunable range of the laser is about 4 GHz around the D1 transition of Rb. The laser frequency tuning is implemented by scanning the FP cavity length. The fluctuation of frequency of the output laser is less than 1 MHz, and the drift of the center frequency is less than 1.5 MHz in 1.5 min. This system has great potential of the application in the experimental investigation of the interaction between light and atoms, especially, for the case of far off the atomic resonance.

利用激光在吸收介质中的非线性像差自散焦效应,设计了一种具有负逻辑功能的无腔全光学双稳系统.本文描述了实验装置和实验结果.给出系统状态的解析公式,得出的理论曲线与实验曲线基本一致.