Infrared laser based on intersubband transitions in quantum wells

In this paper, the current status of intersubband lasing in quantum wells is briefly reviewed, and the physical features related to intersubband infrared lasers are discussed. New device structures based on leaky quantum wells for the realization of intersubband lasing are proposed. It is shown that these newly proposed leaky quantum well device structures are promising for infrared lasers, not only in the creation of population inversion, but also in the suppression of nonradiative loss. Also, some future perspectives are discussed.