Thin-film lasers based on dye-deoxyribonucleic acid-lipid complexes

Amplified spontaneous emission (laser action without cavities) from deoxyribonucleic acid (DNA) derivative films was achieved by doping with a hemicyanine dye which is well known as a nonlinear optical molecule. The amplification confirmed by spectral narrowing and superlinear dependence of the emission intensity on the pumping was observed from the complex films when the film samples were irradiated with a nanosecond laser at the intensity above a threshold value (∼20 μJ). The durability and low threshold values suggest the possibility of DNA complexes as a practical candidate for thin-film dye lasers.