论文标题
非线性相估计通过主动相关的马赫德干涉仪增强
Nonlinear phase estimation enhanced by an actively correlated Mach-Zehnder interferometer
论文作者
论文摘要
非线性相移被引入Mach-Zehnder干涉仪（MZI），我们提出了一种增强相敏性的方案。在我们的方案中，标准MZI的一个输入端口注入了连贯的状态，另一个输入端口则以一种两种模式挤压 - vacuum状态的一种模式注入。使用主动相关输出读数的方法检测到MZI的最终干扰输出。基于光束拆分器的最佳分裂比，相位灵敏度可以超过标准的量子极限并接近量子cramér-rao结合。讨论了光子丢失对相灵敏度的影响。由于非线性相移和Kerr介质的非线性相位移位与易感性$χ^{（3）} $之间的关系，我们的方案还可以提供一些$χ^{（3）} $的单位的估计值。
A nonlinear phase shift is introduced to a Mach-Zehnder interferometer (MZI), and we present a scheme for enhancing the phase sensitivity. In our scheme, one input port of a standard MZI is injected with a coherent state and the other input port is injected with one mode of a two-mode squeezed-vacuum state. The final interference output of the MZI is detected with the method of active correlation output readout. Based on the optimal splitting ratio of beam splitters, the phase sensitivity can beat the standard quantum limit and approach the quantum Cramér-Rao bound. The effects of photon loss on phase sensitivity are discussed. Our scheme can also provide some estimates for units of $χ^{(3)}$, due to the relation between the nonlinear phase shift and the susceptibility $χ^{(3)}$ of the Kerr medium.
