Valley splitting in strained silicon quantum wells modeled with 2 degrees miscuts, step disorder, and alloy disorder

Author

• Neerav Kharche, Birck Nanotechnology Center and Purdue UniversityFollow
• Marta Prada, School of Electrical and Computer Engineering, Purdue UniversityFollow
• Timothy Boykin, Department of Electrical and Computer Engineering, University of Alabama
• Gerhard Klimeck, Purdue UniversityFollow

Abstract

Valley splitting (VS) in strained SiGe/Si/SiGe quantum wells grown on (001) and 2 degrees miscut substrates is computed in a magnetic field. Calculations of flat structures significantly overestimate, while calculations of perfectly ordered structures underestimate experimentally observed VS. Step disorder and confinement alloy disorder raise the VS to the experimentally observed levels. Atomistic alloy disorder is identified as the critical physics, which cannot be modeled with analytical effective mass theory. NEMO-3D is used to simulate up to 10(6) atoms, where strain is computed in the valence-force field and electronic structure in the sp(3)d(5)s(*) model.

Citation

APPLIED PHYSICS LETTERS 90, 092109

Date of this Version

2-26-2007

Recommended Citation

Kharche, Neerav; Prada, Marta; Boykin, Timothy; and Klimeck, Gerhard, "Valley splitting in strained silicon quantum wells modeled with 2 degrees miscuts, step disorder, and alloy disorder" (2007). Birck and NCN Publications. Paper 221.
https://docs.lib.purdue.edu/nanopub/221