Title :
Low-power exciton-based heterojunction bipolar transistors for thresholding logic applications
Author :
Goswami, Subrata ; Hong, Song-Cheol ; Biswas, D. ; Bhattacharya, Pallab K. ; Singh, Jasprit ; Li, Wei-Qi
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA
fDate :
3/1/1991 12:00:00 AM
Abstract :
The principles of an integrated optoelectronic controller-modulator device, based on excitonic transitions and the enhanced Stark effect in quantum wells, are outlined. The device consists of a controller and a modulator as components. The controller is a heterojunction phototransistor with multiquantum wells incorporated in the base-collector depletion region. The amplified output of the controller enables switching of the modulator for low optical power levels. Experimental results on GaAs-AlGaAs based devices, realized by one-step molecular beam epitaxy and selective etching, are presented. The bipolar devices have current gains of ~35-40. The integrating-thresholding properties of the device are demonstrated and switching characteristics for 10 μW input to the controller are measured. Cascadability, optoelectronic amplification, and multistage operation are demonstrated in terms of a fan out of eight devices
Keywords :
III-V semiconductors; aluminium compounds; etching; excitons; gallium arsenide; heterojunction bipolar transistors; integrated optoelectronics; molecular beam epitaxial growth; optical logic; optical modulation; threshold logic; GaAs-AlGaAs; GaAs-AlGaAs based devices; III-V semiconductors; amplified output; base-collector depletion region; bipolar devices; cascadability; current gains; enhanced Stark effect; excitonic transitions; fan out; heterojunction phototransistor; integrated optoelectronic controller-modulator device; integrating-thresholding properties; low optical power levels; low power exciton based heterojunction bipolar transistors; multiquantum wells; multistage operation; one-step molecular beam epitaxy; optoelectronic amplification; quantum wells; selective etching; switching characteristics; thresholding logic applications; Heterojunction bipolar transistors; Logic; Optical bistability; Optical devices; Optical feedback; Optical modulation; Optical pumping; Phototransistors; Quantum well devices; Solid state circuits;
Journal_Title :
Quantum Electronics, IEEE Journal of
