Nonlinear luminescence of high-concentration rhodamine solutions: On the problem of pulsed laser cooling

摘要

The conditions of occurrence of collective photoinduced luminescence in model solutions are determined. The transmittance and luminescence of concentrated solutions of rhodamine 101 under excitation by laser pulses in the Stokes and anti-Stokes spectral ranges are studied. It is shown that, at high pump energies, collective photoinduced luminescence, which competes with induced radiation, plays a significant role in luminescence generation. Temperatures of heating and cooling of solutions are estimated. The photodynamics of cooling of solutions of complex molecules under their pulsed (Stokes and anti-Stokes) excitation is analyzed.