Strain-engineered surface transport in Si(001): complete isolation of the surface state via tensile strain.
Phys Rev Lett
; 111(24): 246801, 2013 Dec 13.
Article
em En
| MEDLINE
| ID: mdl-24483685
ABSTRACT
By combining density functional theory, nonequilibrium Green's function formulism and effective-Hamiltonian approaches, we demonstrate strain-engineered surface transport in Si(001), with the complete isolation of the Si surface states from the bulk bands. Our results show that sufficient tensile strain can effectively remove the overlap between the surface valence state and the bulk valence band, because of the drastically different deformation potentials. Isolation of the surface valence state is possible with a tensile strain of â¼1.5%, a value that is accessible experimentally. Quantum transport simulations of a chemical sensing device based on strained Si(001) surface confirm the dominating surface conductance, giving rise to an enhanced molecular sensitivity. Our results show promise for using strain engineering to further our ability to manipulate surface states for quantum information processing and surface state-based devices.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Phys Rev Lett
Ano de publicação:
2013
Tipo de documento:
Article