Vacuum Confinement Effects on Molecular Dynamics in a Microscopic Cavity

Several experimental schemes of vacuum-confinement in electromagnetic-bounded structures are presented together with related results involving Spontaneously Emitting (SE) molecules. Striking anomalies in the SE spatial-distribution and decay-times are detected. In addition, an anomalous "zero-threshold-laser" behaviour of molecular Stimulated Emission (StE) in a single-mode Casimir-type microscopic cavity is reported. This novel effect is due to an unexpected collective molecular process taking place at an exceedingly low excitation level in the optical-pumping scheme. In the framework of "Phase-transition" theory this effect corresponds to an order-disorder transition taking place at a critical-temperature T c which is virtually infinite.