Abstract

It is shown that a local field effort, i.e. the Lorentz correction E_low- E_mean = 1πp/3, in a dense thermal gas of two-level molecules may give rise to a remarkable antiferroelectric structure with zero macroscopic electric field, E_mean = 0. This is a stationary polarization wave, P(r), of high-frequency molecular dipoles which appears due to the polarization catas trophe well-known for anisotropic crystals, but not for isotropic gases. The electrodynamic mechanism of the dipole self-organization is the soft mode instability at the finite wavelength λ ~ 7πv_T/ω₀, whore v_T is the thermal velocity, and ω₀ is the frequency of molecular transition between the first level and the ground level.

© 1996 IEEE