Title :
Low photocurrent GaAs-Al/sub 0.3/Ga/sub 0.7/As multiple-quantum-well modulators with selective erbium doping
Author :
Yuan, Y. ; Zhang, X. ; Bhattacharya, Pallab
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Michigan Univ., Ann Arbor, MI, USA
Abstract :
A new scheme of reducing the photocurrent of a quantum-confined Stark effect multiple-quantum-well modulator is demonstrated. The GaAs well regions of the 50-period GaAs-Al/sub 0.3/Ga/sub 0.7/As multiple-quantum-well are selectively doped with Er during molecular beam epitaxy to reduce the carrier lifetime to the order of picoseconds. 250-μm diameter mesa-shaped devices have been characterized. The photocurrent responsivity is as low as 0.005 A/W and an extinction ratio greater than 1:8 is achieved at a bias voltage of 8 V.
Keywords :
III-V semiconductors; aluminium compounds; carrier lifetime; electro-optical modulation; electroabsorption; erbium; gallium arsenide; molecular beam epitaxial growth; optical fabrication; photoconductivity; quantum confined Stark effect; semiconductor heterojunctions; semiconductor quantum wells; 250 mum; 8 V; GaAs well regions; GaAs-Al/sub 0.3/Ga/sub 0.7/As; GaAs-Al/sub 0.3/Ga/sub 0.7/As:Er; bias voltage; carrier lifetime; extinction ratio; low photocurrent MQW modulators; mesa-shaped devices; molecular beam epitaxy; multiple-quantum-well; multiple-quantum-well modulators; photocurrent; photocurrent responsivity; quantum-confined Stark effect multiple-quantum-well modulator; Amplitude modulation; Chirp modulation; Erbium; Gallium arsenide; Molecular beam epitaxial growth; Optical modulation; Photoconductivity; Power dissipation; Quantum well devices; Voltage;
Journal_Title :
Photonics Technology Letters, IEEE
