For a direct-gap semiconductor (e.g., a p-n junction), photon-assisted tunneling is known to exhibit a high nonlinear absorption. In a transistor laser, as discussed here, the coherent photons generated at the quantum well interact with the collector junction field and "assist" electron tunneling from base to collector, thus resulting in the nonlinear modulation of the laser and the realization of optical pulse generation. 1 and 2 GHz optical pulses are demonstrated in the transistor laser using collector voltage control.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)