Influence of liquid crystalline phases on the tunability of a random laser
PublisherAmerican Chemical Society (ACS)
Rights accessRestricted access - publisher's policy
In this paper, we report the temperature behavior of an optimized disordered photonic system-based liquid crystal by means of heat capacity and refractive index measurements. The scattering system is formed by a porous borosilicate glass random matrix (about 60%) infiltrated with a smectogenic liquid crystal (about 16%) and a small amount of laser dye (0.1%). The rest of the scattering system is about 24% air, giving rise to a high refractive index contrast scattering system. Such a system has the functionality to change the refractive index contrast with temperature due to the liquid crystal temperature behavior. The system, optically pumped by the second harmonic of a Q-switched Nd:YAG pulsed laser working at 532 nm, exhibits random laser action, the threshold of which depends upon the liquid crystalline mesophase. Temperatures of existence of the smectic- B phase correspond to the most optimized random laser. In such a mesophase, the transport mean free path has been determined as about 16 µm in a coherent backscattering experiment.
CitationTrull, J., Salud, J., Diez, S., Lopez, D. Influence of liquid crystalline phases on the tunability of a random laser. "Physical review E", 30 Maig 2017, vol. 95, núm. 5, p. 052704-1-052704-9.