Abstract

Processes such as self-focusing and degenerate four-wave mixing, which classically can be described in terms of an intensity-dependent refractive index (the optical Kerr effect), appear at the microscopic level to involve momentum exchange among photons, as if there were a photon-photon interaction potential. Within this picture, Kerr optical systems are collections of weakly interacting Bose particles and can be used to investigate a number of interesting problems in condensed matter physics. Indeed, the Nonlinear Schrodinger equations which describe both temporal and spatial soli- tons are formally equivalent to second quantized ϕ⁴ field theories.^1,2

© 1999 Optical Society of America