A six-wave mechanism for second-harmonic generation in isotropic or microscopically disordered media is presented. This mechanism allows the signal to be sustained by molecules of all symmetry types and may also operate in isotropic fluids. A detailed derivation and first explicit result is given for the nonlinear optical susceptibility, solving the problem of secular response.
|Number of pages
|Journal of Physics B: Atomic, Molecular and Optical Physics
|Published - 28 Aug 1997