Abstract
Results are presented of a fully ab initio calculation of impact ionization rates in GaAs within the density functional theory framework, using a screened-exchange formalism and the highly precise all-electron full-potential linearized augmented plane wave method. The calculated impact ionization rates show a marked orientation dependence in k space, indicating the strong restrictions imposed by the conservation of energy and momentum. This anisotropy diminishes as the impacting electron energy increases. A Keldysh type fit performed on the energy-dependent rate shows a rather soft edge and a threshold energy greater than the direct band gap. The consistency with available Monte Carlo and empirical pseudopotential calculations shows the reliability of our approach and paves the way to ab initio calculations of pair production rates in new and more complex materials.
| Original language | English |
|---|---|
| Article number | 113206 |
| Pages (from-to) | 1132061-1132064 |
| Number of pages | 4 |
| Journal | Physical Review B - Condensed Matter and Materials Physics |
| Volume | 65 |
| Issue number | 11 |
| Publication status | Published - Mar 15 2002 |
Fingerprint
ASJC Scopus subject areas
- Condensed Matter Physics
Cite this
Impact ionization in GaAs : A screened exchange density-functional approach. / Picozzi, Silvia; Asahi, R.; Geller, C. B.; Continenza, A.; Freeman, Arthur J.
In: Physical Review B - Condensed Matter and Materials Physics, Vol. 65, No. 11, 113206, 15.03.2002, p. 1132061-1132064.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Impact ionization in GaAs
T2 - A screened exchange density-functional approach
AU - Picozzi, Silvia
AU - Asahi, R.
AU - Geller, C. B.
AU - Continenza, A.
AU - Freeman, Arthur J
PY - 2002/3/15
Y1 - 2002/3/15
N2 - Results are presented of a fully ab initio calculation of impact ionization rates in GaAs within the density functional theory framework, using a screened-exchange formalism and the highly precise all-electron full-potential linearized augmented plane wave method. The calculated impact ionization rates show a marked orientation dependence in k space, indicating the strong restrictions imposed by the conservation of energy and momentum. This anisotropy diminishes as the impacting electron energy increases. A Keldysh type fit performed on the energy-dependent rate shows a rather soft edge and a threshold energy greater than the direct band gap. The consistency with available Monte Carlo and empirical pseudopotential calculations shows the reliability of our approach and paves the way to ab initio calculations of pair production rates in new and more complex materials.
AB - Results are presented of a fully ab initio calculation of impact ionization rates in GaAs within the density functional theory framework, using a screened-exchange formalism and the highly precise all-electron full-potential linearized augmented plane wave method. The calculated impact ionization rates show a marked orientation dependence in k space, indicating the strong restrictions imposed by the conservation of energy and momentum. This anisotropy diminishes as the impacting electron energy increases. A Keldysh type fit performed on the energy-dependent rate shows a rather soft edge and a threshold energy greater than the direct band gap. The consistency with available Monte Carlo and empirical pseudopotential calculations shows the reliability of our approach and paves the way to ab initio calculations of pair production rates in new and more complex materials.
UR - http://www.scopus.com/inward/record.url?scp=0012105723&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0012105723&partnerID=8YFLogxK
M3 - Article
VL - 65
SP - 1132061
EP - 1132064
JO - Physical Review B-Condensed Matter
JF - Physical Review B-Condensed Matter
SN - 1098-0121
IS - 11
M1 - 113206
ER -