Theory of the Single Susceptibility equally associated with Non-radiative and Radiative Fields in Optics IV

Robert W. Boyd

Kikuo Ujihara

Chaotic fields in a general class of one-dimensional optical cavity having output coupling is considered. The fluctuation-dissipation theorem is derived assuming that the cavity materials are lossless. The cavity admittance probed by a prescribed current source for an arbitrarily stratified optical cavity is calculated and using the explicit expression for the admittance the “dissipation” is proved to be equal to the radiation loss. The form of the fluctuation-dissipation theorem for a restricted frequency region around a cavity mode is discussed with particular attention to the cavity mode degeneracy.

Robert W. Boyd

Suzanne Giraud-Cotton, V.Paul Kaftandjian, B. Talin

The theory of Doppler-free magnetic optical activity associated with a single absorption line is presented. The transmission of tunable laser light, linearly polarized, through a dilute gaseous medium along a steady magnetic field is studied in the presence of a second counterpropagating saturating laser. The third order non linear susceptibility is calculated for a two-level system exhibiting a normal Zeeman effect, with arbitrary J values.

Kochise Bennett, Shaul Mukamel

The semi-classical theory of radiation-matter coupling misses local-field effects that may alter the pulse time-ordering and cascading that leads to the generation of new signals. These are then introduced macroscopically by solving Maxwell's equations. This procedure is convenient and intuitive but ad hoc. We show that both effects emerge naturally by including coupling to quantum modes of the radiation field that are initially in the vacuum state to second order. This approach is systematic and suggests a more general class of corrections that only arise in a QED framework. In the semi-classical theory, which only includes classical field modes, the susceptibility of a collection of N non-interacting molecules is additive and scales as N. Second-order coupling to a vacuum mode generates an effective retarded interaction that leads to cascading and local field effects both of which scale as N(2).