Abstract
Interface disorder and its effect on valley degeneracy in the conduction band present an important theoretical challenge for operating spin qubits in silicon. Here, we demonstrate and investigate a counterintuitive effect occurring at interfaces. By applying tight-binding methods, we show that intrinsic interface states can hybridize with conventional valley states to produce an anomalously large ground-state energy gap. Such hybridization effects have not previously been explored in detail for valley splitting. We find that the splitting can be enhanced by disorder in the chemical bonds at the interface, in agreement with recent experiments.
- Received 22 November 2010
DOI:https://doi.org/10.1103/PhysRevB.82.245314
©2010 The American Physical Society