The role of the thermally modulated order parameter in the diffusive laser action observed in dye doped nematic liquid crystals was investigated. Above a given pump energy a randomly distributed series of bright tiny spots appear, giving rise to a strongly fluctuating emission pattern. The spectral analysis reveals discrete sharp peaks (about 0.5 nm) slightly blueshifted with respect to the highest efficiency region of the gain medium. A comparative study was performed in systems having different sizes and confining geometries, corroborating the idea that the random lasing observed in dye doped nematic phase is fluctuation driven through a recurrent multiple scattering process. (c) 2006 American Institute of Physics.
Thermal behavior of random lasing in dye doped nematic liquid crystals
A. DE LUCA;C. C. VERSACE;Scaramuzza N.;R. BARTOLINO;G. STRANGI
2006-01-01
Abstract
The role of the thermally modulated order parameter in the diffusive laser action observed in dye doped nematic liquid crystals was investigated. Above a given pump energy a randomly distributed series of bright tiny spots appear, giving rise to a strongly fluctuating emission pattern. The spectral analysis reveals discrete sharp peaks (about 0.5 nm) slightly blueshifted with respect to the highest efficiency region of the gain medium. A comparative study was performed in systems having different sizes and confining geometries, corroborating the idea that the random lasing observed in dye doped nematic phase is fluctuation driven through a recurrent multiple scattering process. (c) 2006 American Institute of Physics.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.