Abstract:

In this paper, the phase estimation limits of an active-related Mach-Zehnder interferometer with three port inputs and two different input states was studied using quantum Fisher information and quantum Fisher information matrix theory. In the case of an arbitrary light field input to a single port, the effect of the input field fluctuation on the limit of phase estimation is eliminated by the theory of phase averaging and the quantum Fischer information matrix. In the case of a dual port input coherent state, the effect of the fluctuating light field on the estimation limit cannot be eliminated, and the phase estimation limit depends on the initial phase of the two input coherent states.

Key words: actively correlated Mach-Zehnder interferometer, quantum Fisher information matrix, phase estimation, nonlinear beam splitter