Bandgap Restructuring of the Layered Semiconductor Gallium Telluride in Air
Jose J Fonseca1,2, Sefaattin Tongay1, Mehmet Topsakal3
1Department of Materials Science and Engineering, University of California, Berkeley, CA, 94720, USA.
Advanced Materials (Deerfield Beach, Fla.)
|May 13, 2016
Abstract:
A giant bandgap reduction in layered GaTe is demonstrated. Chemisorption of oxygen to the Te-terminated surfaces produces significant restructuring of the conduction band resulting in a bandgap below 0.8 eV, compared to 1.65 eV for pristine GaTe. Localized partial recovery of the pristine gap is achieved by thermal annealing, demonstrating that reversible band engineering in layered semiconductors is accessible through their surfaces.
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