Tunneling-induced high-efficiency four-wave mixing in asymmetric quantum wells

An asymmetric double quantum well (QW) structure with resonant tunneling is suggested to achieve highly efficient four-wave mixing (FWM). We analytically demonstrate that resonant tunneling can induce a highly efficient mixing wave in such a semiconductor structure with a low-light pump wave. In particular, the FWM conversion efficiency can be enhanced dramatically in the vicinity of the center frequency with small propagation distance. This interesting scheme may be used to generate coherent long-wavelength radiation in solidstate systems.