Abstract

Multiquantum well structures of GaSb wells down to 12-Å width, separated by 120-Å AlSb barriers, were grown by molecular beam epitaxy, and their low-temperature photoluminescence was studied. Even though GaSb should become an indirect-gap semiconductor for well widths below about 90 Å, the direct-gap luminescence persists to the narrowest wells. The shift of photon energy with well width indicates strong nonparabolicity effects; it is in good agreement with Bastard’s simple model of quantum wells in nonparabolic semiconductors. For wells less than 45 Å wide, the direct-gap luminescence is accompanied by a strong and very broad lower-energy luminescence peak, which appears to be related to electron accumulation in the X valleys, but the exact mechanism for which is not clear. A two-electron transition model is proposed.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.