Measurement of phase differences between two partially coherent fields

Abstract

Although the operational approach to the quantum-phase problem developed earlier by us [Phys. Rev. A 45, 424 (1992)] has now been confirmed experimentally for several different states of the electromagnetic field, so far no measurements have been reported with partially coherent light beams. This situation is remedied in the present work, where we report the results of measurements on light obeying thermal statistics with a variable degree of mutual coherence. Once again, we find agreement between experiment and our theoretical approach.