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^‡

The negativity volume of Winger function versus the encoding phase (a) with different ∣ α 0 ∣ , parameters: r=1.5, g=0.2; (b) with different squeezing parameters r, parameters: ∣ α 0 ∣ = 2 , g=0.2; (c) with different gain coefficients g, parameters: ∣ α 0 ∣ = 2 , r=1.5.