Epitaxial Growth and Characterization of Topological Alpha-Sn and Alpha-Sn1-xGex Films
Abstract
Epitaxial single crystal films of alpha-tin and alpha-tin alloyed with germanium have been grown using molecular beam epitaxy on indium antimonide surfaces. By alloying with germanium, the strain in films could be controlled from compressive to tensile. The resulting electronic structure of the films was studied using angle-resolved photoelectron spectroscopy, scanning tunneling microscopy and spectroscopy without exposure to air, and cryogenic temperature magnetotransport. Preliminary results confirm that thin films of alpha-tin alloyed with germanium are topological insulators. Further, tensile strain does not appear to open an energy gap in the alpha-Sn surface states intrinsically, but the gap is actually a result of either band occupation or lattice distortion. It was also found that alpha-tin growth on antimony-terminated indium antimonide surfaces decreased indium segregation and thus widened the growth window.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 21, 2022
- Accession Number
- AD1189818
Entities
People
- Chris J. Palmstrøm
Organizations
- University of California Regents