Lasing in DNA-CTMA doped with Rhodamine 610 in butanol.

The light emission properties of the complex formed from deoxyribonucleic acid (DNA)-cetyltrimethylammonium chloride (CTMA) surfactant doped with different concentrations of Rhodamine 610 (Rh610) dye and dissolved in butanol are investigated and discussed. The results are compared to those obtained when only the Rh610 dye is dissolved in butanol, at the same concentrations. The light emission is excited in the investigated samples by the nanosecond pulses of a frequency-doubled Nd:YAG laser, at a wavelength of 532 nm. We have demonstrated the lasing effect in the investigated complex and we have studied its efficiency and coherence properties. The lasing properties of the Rh610 dye are favourably influenced by the presence of the DNA-CTMA complex in the investigated compound. It leads to an increase in the lasing efficiency and in the slope efficiency. Also the temporal coherence of the emitted light is larger and the emission can be tuned to shorter wavelengths.