Analysis and improvement of optical frequency response in a long wavelength transistor laser

Abstract

Charge control model and rate equations have been exploited for the first time in order to glean the optical frequency response of a long-wavelength heterojunction bipolar transistor laser. For a 1.56 μm N-InP/p-InAlGaAs/N-InP fabricated transistor laser with a single quantum well, the optical bandwidth is estimated using this model. All parameters of the mentioned model have been computed for this new type of long wavelength transistor laser. It has been found that frequency response of this optoelectronic device has a 29 dB resonance peak which is not very desirable and is so higher than traditional GaAs transistor lasers. Furthermore, we have illustrated that the resonance peak will decrease and the optical bandwidth will increase, if we increase the width of the quantum well. Finally, we have analyzed that how base width affects on the optical bandwidth and resonance peak of frequency response. It has been proved that, there is a trade-off between larger bandwidth and lower resonance peak for base width effect.