Properties of lasing in Rhodamine 6G solutions with nanoparticles free of plasmon resonance

Abstract

The threshold characteristics of lasing in a 20-μm layer of colloidal solution of Rhodamine 6G dye with plasmon-resonance Au nanoparticles and non-plasmon-resonance Pt nanoparticles excited by 532-nm radiation are experimentally studied. The spectral dependence of the scattering and absorption cross sections of gold and platinum nanoparticles are calculated within the Mie theory. It is found experimentally that the addition of nanoparticles to the active medium decreases the lasing thresholds by two orders of magnitude. It is shown that the lasing thresholds are 1.5–2 times lower when adding gold nanoparticles than when adding platinum nanoparticles of the same concentration.