PHASE PROPERTIES OF THE QUANTIZED SINGLE-MODE ELECTROMAGNETIC-FIELD - COMMENT

We show that the approach by Pegg and Barnett [Phys. Rev. A 39, 1665 (1989)] to construct a phase operator through a limiting procedure does not give a satisfactory description of the phase properties of the quantized electromagnetic field. We refute the claim that their approach predicts the same results of physical experiments on phase properties as the conventional Hilbert space approach. Their procedure could only be used as a definition of the phase, but it is not a good definition because the "phase" states they used to construct their "phase" operator are not of precisely defined phase contrary to their assertion.