  The work was aimed to generate random laser emissions simultaneously at two
wavelengths in a weakly scattering system containing mixture of binary dyes,
rhodamine-B (Rh-B) and oxazine-170 (O-170) dispersed with ZnO nano-particles
served as scattering centres. Random lasing performances for individual Rh-B
dye were extensively studied for varying small signal gain/scatterer density
and found lasing threshold significantly depend upon number density of
dispersed nano-particles. In spite of inefficient pumping, we demonstrated
possibility of random lasing in O-170 dye solution on account of resonance
energy transfer from Rh-B dye served as donor. At optimum concentrations of
fluorophores and scatterer in dye mixture solution, incoherent random lasing
was effectively attained simultaneously at two wavelengths centered 90 nm
apart. Dual-emission intensities, lasing thresholds and rate of amplifications
were found to be equivalent for both donor and acceptor in dye mixture
solution.
