基于马赫-曾德尔干涉仪的单个光子操控

分别利用空间和光纤马赫—曾德尔干涉仪对空间和光纤传输中的单个光子的干涉现象进行了研究，干涉对比度可达到90％以上，实现了空间和光纤中的单个光子的路由操控。实验采用脉冲调制加衰减的方法产生单个光子，获得了每个脉冲中只包含0．1个光子的准单光子源。通过改变压电换能器的电压控制马赫—曾德尔干涉仪的单个光子在两个输出端的选择，实现了光子在节点上的路由。采用同步符合检测技术，利用重复频率为1kHz，脉冲宽度为100ns的同步信号对输出信号进行符合，实现了量子效率高于70％，暗计数小于0．2s^-1的单光子高灵敏度检测，观测到了单个光子在相位操控下出射到两个输出端的有序分配现象。验证了基于马赫—曾德尔干涉仪的单个光子路由操控实现的可能性。

Single-Photon Control with Mach-Zehnder Interferometer

Research is done on the single|photon interference with two different Mach Zehnder (M Z) interferometers particle and fiber separately. Achieving the high contrast above 90%, the experiment approves the routing control of single photon with Mach Zehnder interferometers of particle and fiber successfully. Pulse modulating and attenuating techniques are implemented to get the single photon, and the subsingle|photon source is achieved with only 0.1 photon in one pulse. The routing control of the single photon is under the control of the changing of PZT power. Furthermore, the synchronous single photon coincidence detection technique is used to detect the single photon, modulation with repeating frequency of 10 kHz and pulse FWHM of 100 ns, the high sensitive detection is improved with high quantum efficiency over 70% and the dark count below 0.2 s -1 , single|photon output through the chosen path with given chosen PZT power has been observed. The experiment verifies that single|photon routing control can be achieved in Mach Zehnder interference.