Title :
AlGaAs-GaAs multiple-quantum-well spectrally tunable photoconductors
Author :
Youn, Hyoung J. ; Darling, Robert B. ; Kuhn, Kelin J.
Author_Institution :
Dept. of Electr. Eng., Washington Univ., Seattle, WA, USA
Abstract :
AlGaAs-GaAs multiple-quantum-well (MQW) photoconductors were fabricated and compared to bulk GaAs-based photoconductors. Dark and illuminated responses were measured to investigate the effectiveness of the AlGaAs window and AlGaAs buffer layers. The spectral response of the MQW photoconductors shows 40 nm of absorption edge shift (material tunability) to shorter wavelengths than those of bulk photoconductors and an excellent spectral rejection near the absorption edge (23 dB). The feasibility of the electrical tunability of MQW photoconductors via the quantum confined Stark effect (QCSE) was also investigated. A very small amount of electrical tunability was obtained with this structure, but the effect of the built-in electric field must be reduced in order to achieve the full spectral shift that is possible with the QCSE.<>
Keywords :
III-V semiconductors; Stark effect; aluminium compounds; gallium arsenide; photoconducting materials; semiconductor quantum wells; AlGaAs buffer layers; AlGaAs window; AlGaAs-GaAs; AlGaAs-GaAs MQW spectrally tunable photoconductors; III-V semiconductor; absorption edge shift; dark responses; electrical tunability; illuminated responses; material tunability; quantum confined Stark effect; spectral rejection; spectral response; Absorption; Buffer layers; Conducting materials; Gallium arsenide; Photoconducting materials; Photoconductivity; Potential well; Quantum well devices; Stark effect; Substrates;
Journal_Title :
Photonics Technology Letters, IEEE
