Abstract

The total noise of a state is the sum of the fluctuations in the real part of the field amplitude and those in the imaginary part. It is a measure of the total fluctuations in the field amplitude and is a minimum for coherent states. Several examples of nonclassical fields are considered, and it is shown that as nonclassical behavior increases so does total noise. For example, total noise increases as a state becomes more squeezed or as the photon statistics become more sub-Poissonian. This result is then generalized by using the concept of nonclassical distance. Nonclassical distance δ is a measure of the extent to which the behavior of a field state differs from that of classical states. A lower bound for the total noise is derived which is an increasing function of δ. This means that the more nonclassical a state is the greater its total noise must be.

© 1988 Optical Society of America