SELF-HOMODYNE TOMOGRAPHY OF A TWIN-BEAM STATE

A self-homodyne detection scheme is proposed to perform two-mode tomog raphy on a twin-beam state at the output of a nondegenerate optical pa rametric amplifier. This scheme has been devised to improve the matchi ng between the local oscillator and the signal modes, which is the mai n limitation to the overall quantum efficiency in conventional homodyn ing. The feasibility of the measurement is analyzed on the basis of Mo nte Carlo simulations, studying the effect of nonunit quantum efficien cy on detection of the correlation and the total photon-number oscilla tions of the twin-beam state.