QUANTUM STATE MEASUREMENT BY REALISTIC HETERODYNE-DETECTION

The determination of the quantum properties of a single-mode radiation field by heterodyne or double homodyne detection is studied. The real istic case of not fully efficient photodetectors is considered. It is shown that a large amount of quite precise information is available, w hereas the completeness of such information is also discussed. Some ex amples are given and the special case of states expressed as a finite superposition of number states is considered in some detail.