Abstract

The possibility of exploiting the dynamic electron-nucleus interaction to create a nuclear population inversion in a short-lifetime excited state has been discussed,¹ and work on some models incorporating nonlinear or nonperturbative approaches continues. In addition, there is also recent interest in the question of whether the superradiant effect is observable in nuclear gamma transitions from such an inversion.² Here we examine the symmetry effect which leads to the N or N² dependence of enhanced spontaneous emission described by Dicke in boson fields as applied to nuclear transitions. Recent laser approaches treating nuclear superradiance as a transient laser pulse involving stimulated emission do not examine that symmetry. A classification scheme based on the unitary and permutation groups is used to describe basic decay rate characteristics, spatial dependence of the cooperation number, and multilevel effects in the short-wavelength regime.

© 1987 Optical Society of America