Title :
Electrooptic effects in GaAs-AlGaAs narrow coupled quantum wells
Author :
Earnshaw, M.P. ; Allsopp, D.W.E.
Author_Institution :
Dept. of Electron., York Univ., UK
Abstract :
The linear and quadratic electrooptic coefficients in narrow single and strongly coupled GaAs-AlxGa1-xAs quantum wells have been measured. The quadratic electrooptic effect is enhanced over that of conventional square quantum wells for both TE and TM polarization in all the structures considered, by up to six times in the case of 2-nm-wide GaAs-Al0.2Ga0.8As strongly coupled quantum wells. The origin of the enhanced quadratic electrooptic effect was found to correlate with a larger red shift in the absorption edge exciton and strong Coulombic coupling of the bound exciton states with the quasi-continua
Keywords :
III-V semiconductors; aluminium compounds; electro-optical effects; electroabsorption; excitons; gallium arsenide; light polarisation; red shift; semiconductor quantum wells; 2 nm; GaAs-Al0.2Ga0.8As; GaAs-Al0.2Ga0.8As strongly coupled quantum wells; GaAs-AlGaAs; GaAs-AlGaAs narrow coupled quantum wells; TE polarization; TM polarization; absorption edge exciton coupling; bound exciton states; electroabsorption; electrooptic effects; electrorefraction; linear electrooptic coefficients; narrow single GaAs-AlxGa1-xAs QW; quadratic electrooptic coefficients; quasi-continua; red shift; strong Coulombic coupling; strongly coupled GaAs-AlxGa1-xAs QW; Absorption; Electrooptic effects; Excitons; Optical modulation; Optical refraction; Optical variables control; Phase modulation; Polarization; Switches; Tellurium;
Journal_Title :
Quantum Electronics, IEEE Journal of
