Abstract

Since quantum nondemolition (QND) measurement was proposed by Braginsky,¹ the possibility of QND measurement in optics has been intensively discussed^2-5. One of the authors of this paper proposed a QND measurement of a. photon number using the optical Kerr effect.³ In this treatment, however, a usual quantum mechanical description was adopted that describes temporal evolution of spatial modes but is not suited for the description of spatial evolution of an optical wave in open space. In addition, photon dissipation, which is inevitable in a. real environment, has not yet been considered in the QND measurement theory.

© 1988 Optical Society of America