Magneto-optical spaser
  We present an electrodynamical model of a novel quantum plasmonic device - magneto-optical spaser. It is shown that a spherical gain nanoparticle coated with a metallic magneto-optical shell can operate as a spaser amplifying circularly polarized surface plasmons. The magneto-optical spaser may be used in design of optical isolator in plasmonic transmission lines as well as in spaser spectrometry of chiral molecules. 
D. G. Baranov, A. P. Vinogradov, A. A. Lisyansky, Yakov M. Strelniker,   and David J. Bergman
cond-mat.mes-hall physics.optics