The criteria for lasing in a dielectric sphere surrounded by an active medium are given. They are presented in simple analytical form and confirmed by numeric calculations of the amplitudes of the morphology-dependent resonances in spontaneous emission spectra. The determined lasing threshold of this novel-type laser is compared with that of a conventional spherical laser with an optically active internal layer. The diverse advantages of a laser based on the gain of the evanescent part of a whispering-gallery mode are discussed.
© 2005 Optical Society of America
Vitaly V. Datsuyk, Saulius Juodkazis, and Hiroaki Misawa, "Properties of a laser based on evanescent-wave amplification," J. Opt. Soc. Am. B 22, 1471-1478 (2005)