Whispering-gallery microlasers doped with plasmonic nanoparticles

Abstract

Whispering gallery mode (WGM) microlasers were obtained by impregnating polystyrene microspheres in an aqueous solution of plasmonic nanoparticles and Rhodamine 6G. The emission spectra of Rhodamine-doped microspheres with diameters of 1 μm and 5-7 μm exhibited peaks corresponding to WGM, with a low Q-factor for 1-μm and a higher Qfactor for 5-7-μm spheres. The embedding of gold nanoparticles into microlasers results in a 40% decrease in the WGM intensity, while doping with silver nanoparticles increases it by 10%.