TRANSVERSE QUANTUM CORRELATIONS, STIMULATED-EMISSION AND EINSTEIN CAUSALITY IN THE ACTIVE OPTICAL MICROCAVITY

An extended theoretical and experimental analysis is reported of the c lassic problem, first discussed by E Fermi, of the interaction between two quantum systems A and B. In our case, the two systems are confine d within an optical microcavity and the interaction takes place in the transverse direction, i.e. orthogonal to the only k-wavevector allowe d by the cavity with the minimum spacing d = 1/2 lambda(O). In these c onditions, our theory analyses in detail the process of two-atom super -radiance. The experiment consists of an investigation, by the use of a femtosecond laser, of the process of coupling of two microlasers act ive over the same transverse mode of an optical microcavity.