Absence or existence of intrinsic optical bistability of coupled ion pairsin solids

There has been a number of papers [2-4,8] published which deal with the pre diction of intrinsic optical bistability of coupled ion pairs in a coherent radiation held. This coupling can be different, either electromagnetic nea r-held coupling of the transition dipoles or other more general interaction s. In the last year Malyshev et al. published a paper in which the authors deny the existence of this bistability. In this paper the reason is discuss ed for this discrepancy, which seems to be due to different approaches of i ntroducing the external phase destroying perturbations. The bistability is based on an inversion-dependent resonance frequency of coupled ions which c an generally be important for phase-sensitive effects. (C) 2000 Elsevier Sc ience S.A. All rights reserved.