Towards stimulated generation of coherent plasmons in nanostructures

A possible generation scheme for growing coherent plasma oscillations (plas ma instability) is presented. Specific quantum well structures, where a suf ficient population inversion can be maintained in the carrier distribution by appropriate injection-extraction configurations, form the basis of this scheme. Self-consistent random phase approximation calculations show that a population inversion, leading to a plasma instability, can occur in such s tructures. A comparison between the calculated and the observed differentia l conductance curves suggests that such quantum well structures could be de signed as active regions for the generation of terahertz frequency radiatio n sources. (C) 1999 American Institute of Physics. [S0021-8979(99)05207-X].