Patent ID: 7569188
Filing Date: 2009-08-04
Classification: B82Y,G01N,H01S

Abstract:
1. An apparatus for generating a nanoscale oscillating electric field via surface plasmon amplification by stimulated emission of radiation (SPASER), comprising: a resonant medium having at least one surface plasmon mode therein; an active medium, having a transition frequency and comprising at least one object having a significant transition strength; and an energy source; wherein the application of energy from the energy source to the active medium results in the energy transition of the at least one object, thereby causing population inversion in the active medium and stimulating the emission of the at least one surface plasmon in the resonant medium, and wherein the energy source provides a power exceeding a threshold so as to satisfy the SPASER action condition αn >0, where αn=(An−γn)/γn is a dimensionless gain, γn is the relaxation rate of the at least one surface plasmon mode, and A is Einstein's coefficient describing the net stimulated emission rate of the at least one surface plasmon mode, An being proportional to said transition strength and to a spatial overlap factor between said population inversion and the intensity of said at least one surface plasmon mode, whereby said SPASER action causes the buildup of a macroscopic number of surface plasmons in the at least one surface plasmon mode.