Physical Review A
Transverse distribution of quantum fluctuations and correlations in spatial solitons
Nicolas Treps, Claude Fabre
Abstract
We give in this paper a general method by which to determine the transverse spatial distribution of quantum fluctuations in a light beam as it propagates through a nonlinear medium. We apply this method to the particular case of spatial solitons that propagate without distortion in ${\ensuremath{\chi}}^{(2)}$ or ${\ensuremath{\chi}}^{(3)}$ materials. We find, for example, that in the ${\ensuremath{\chi}}^{(2)}$ case the central part of the soliton has lower intensity quantum fluctuations than its outer part, and that in most cases strong correlations develop among the field quadrature components measured in different areas of the transverse plane.