Generation of nonclassical light and quantum nondemolition measurement by optical fibers with a spatially periodic energy exchange between two modes

The generation of nonclassical states of light in optical fibers with a spatial beating of the energy for traveling modes is considered. The effects of quantum squeezing and correlation of photons for two types of optical fibers, i.e. for tunnelly-coupled (dual-core) and for spatially nonhomogeneous fibers, are studied. It is shown that in the field of ordinary CW He-Ne laser at intensity of 100 W/cm2 the suppression of quantum (vacuum) fluctuations of one of the field quadrature components may obtain of a value about ten percent. The possibilities of experimental realization both of suggested scheme for the squeezed states generation and of carrying out of quantum non-demolition measurement are discussed.