Fig. 4From: A photon counting and a squeezing measurement method by the exact absorption and dispersion spectrum of Λ-type Atoms(Color online) a Dispersion and b absorption for different squeezing parameters and the number of coupling photons is n2 = 100. c Dispersion and d absorption for different squeezing parameters for vacuum coupling field (squeezing parameters are r = 0, 0.2, 0.4, 0.6, 0.8, 1, 1.2, 1.4, 1.6, 1.8, 2)Back to article page