4.3 GHz optical bandwidth light emitting transistor

Abstract

We demonstrate a quantum-well base heterojunction bipolar light emitting transistor (HBLET) operating in the common collector configuration with a 3 dB optical response bandwidth f3 dB of 4.3 GHz. The HBLET has a current gain, β (=|ΔIC/ΔIB|) as high as 30, and can be operated as a three-port device to provide simultaneously an optical and electrical output with gain. The f3 dB of 4.3 GHz corresponds to an effective carrier recombination lifetime of 37 ps, and shows that “fast” spontaneous recombination can be harnessed for high-speed modulation.