Abstract: | Thefourth-order quantum interference of squeezed fields generated by two independent opticalparametric oscillators(OPOs) is discussed based on the semi-classical theory. It is shownthat at the oscillation threshold of OPOs the squeezing of two output fields is thehighest but the fringe visibility of fourth-order interference is the lowest(33.3%). Whenthe pump power is away from the threshold, the squeezing decreases while the correlationbetween them increases. |