2010/06/30 by A. L. Saraiva, André Saraiva, M. J. Calderón +4 · 2 citations
Engineering · Physics and Astronomy · #Bound state #Condensed matter physics #Coupling (piping) #Degeneracy (biology) #Effective mass (spring–mass system) #Electron #Excited state #Materials science #Physics #Quantum and electron transport phenomena #Quantum mechanics #Semiconductor Quantum Structures and Devices #Semiconductor materials and devices #Thermal conduction #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.84.155320
published as Phys. Rev. B 84, 155320 (2011) · 11 pages, 3 figures, 2 tables
openalex publication_date 2011/10/27 · arxiv created 2011/11/14 · arxiv updated 2011/11/15 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Orbital degeneracy of the electronic conduction band edge in silicon is a potential roadblock to the storage and manipulation of quantum information involving the electronic spin degree of freedom in this host material. This difficulty may be mitigated near an interface between Si and a barrier material, where intervalley scattering may couple states in the conduction ground state, leading to nondegenerate orbital ground and first excited states. The level splitting is experimentally found to have a strong sample dependence, varying by orders of magnitude for different interfaces and samples. The basic physical mechanisms leading to such coupling in different systems are addressed. We expand our recent study based on an effective mass approach, incorporating the full plane-wave expansions of the Bloch functions at the conduction band minima. Physical insights emerge naturally from a simple Si/barrier model. In particular, we present a clear comparison between ours and different approximations and formalisms adopted in the literature and establish the applicability of these approximations in different physical scenarios.