Theoretically exploring the phase precision in a noisy Mach-Zehnder interferometer
Duan Xie, Chen Haifeng · Journal of the Korean Physical Society · 2017
This paper presents the phase precision of a Mach-Zehnder interferometer in the presence of two types of quantum noise. Under the influence of amplitude-damping noise, the precisions of three input cases will gradually decrease and be less than the standard quantum limit. When the quantum states are influenced by bit-phase flip, the precisions for inputs of a coherent state and a squeezed vacuum state and the precision of spin squeezing state decrease at first and then increase with increasing η (parameter characterizing the noise strength) from 0 to 1. Comparing the rates at which the precisions decrease, we found that the precision of the spin squeezing state decreased faster than those of the other two cases in most instances.