Repeatable two-mode phase measurement

A measurement scheme to perform a repeatable phase detection on a two-mode field is presented. The interaction with the probe state (the output state of a phase-insensitive high-gain amplifier) is described by a Hamiltonian which is physically realizable in the rotating wave approximation. Information on the system is obtained through unconventional heterodyne measurements performed on the probe field after the interaction with the system. The expressions for the probability distribution and the state reduction are given.