Spasing and amplification in plasmonic nanosystems

Surface plasmon amplification by stimulated emission of radiation (spaser) is a nanoscopic quantum generator of coherent local optical fields with high intensity. We will consider the latest development in the theory of spaser and review the large number of experimental data currently available Nanoplasmonics deals with collective electron dynamics on the surface of metal nanostructures, which arises due to excitations called surface plasmons [1, 2]. The surface plasmons localize and concentrate optical energy in nanoscopic regions creating highly enhanced local optical fields. They undergo ultrafast dynamics with timescales as short as a few hundred attoseconds [3]. We will start with a brief overview of the state of nanoplasmonics and its many applications [2].