Population-inversion and gain estimates for a semiconductor TASER

We have investigated a solid-state design advanced (see Soref et al. in SPIE Proceedings, vol.3795, p.516, 1999) to achieve a terahertz-amplification-by-the-stimulated-emission-of-radiation (TASER). The original design was based on light-to heavy-hole intersubband transitions in SiGe-Si heterostructures. This work adapts the design to electron intersubband transitions in the more readily available GaAs/Ga/sub 1-x/Al/sub x/As material system. It is found that the electric-field induced anti-crossings of the states, derived from the first excited state with the ground states of a superlattice in the Stark-ladder regime, offers the possibility of a population inversion and gain at room temperature.