Patent ID: 7486437

Claim:
A method for achieving optical amplification of an optical signal passing through indirect-gap semiconductor, the method comprising the steps of: (a) providing a body of the indirect-gap semiconductor doped with at least one element so as to generate at least one added energy level at a known energy lying within the energy band-gap of the semiconductor, said added energy level enabling an energy transition between said added energy level and an energy band of the semiconductor corresponding to generation of a photon of a given wavelength, wherein said indirect-gap semiconductor is silicon, and wherein said at least one element is chosen from the group comprising: Gold, Silver, Platinum, Iron, Copper, Zinc, Cobalt, Tellurium, Mercury, Nickel, Sulfur and Manganese; and (b) irradiating a target region of said body of semiconductor with optical illumination of a wavelength shorter than said given wavelength in such a manner as to cause population inversion of charge carriers within the target region, thereby causing amplification of an optical signal of said given wavelength within said target region.