Negativity of Wigner function and phase sensitivity of an SU(1,1) interferometer

Liu Chun-Li, Guo Li-Li, Zhang Zhi-Ming^†, Yu Ya-Fei^‡

Comparison of the phase sensitivity with the Heisenberg limit (HL) and the shot noise limit (SNL). Parameters: ∣ α 0 ∣ = 2 , r = 1.