Abstract
We present the results of a fully first-principles calculation of impact ionization rates in GaAs within the density functional theory formalism, using a screened-exchange approach and the highly accurate all-electron full-potential linearized augmented plane wave (FLAPW) 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 |
|---|---|
| Pages (from-to) | 421-424 |
| Number of pages | 4 |
| Journal | Journal of Computational Electronics |
| Volume | 1 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - Oct 1 2002 |
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Keywords
- density functional theory
- GaAs
- impact ionization
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Modelling and Simulation
- Electrical and Electronic Engineering
Cite this
Impact Ionization in GaAs within A Screened Exchange Density Functional Formalism. / Picozzi, S.; Asahi, R.; Geller, C. B.; Freeman, A. J.
In: Journal of Computational Electronics, Vol. 1, No. 3, 01.10.2002, p. 421-424.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Impact Ionization in GaAs within A Screened Exchange Density Functional Formalism
AU - Picozzi, S.
AU - Asahi, R.
AU - Geller, C. B.
AU - Freeman, A. J.
PY - 2002/10/1
Y1 - 2002/10/1
N2 - We present the results of a fully first-principles calculation of impact ionization rates in GaAs within the density functional theory formalism, using a screened-exchange approach and the highly accurate all-electron full-potential linearized augmented plane wave (FLAPW) 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 - We present the results of a fully first-principles calculation of impact ionization rates in GaAs within the density functional theory formalism, using a screened-exchange approach and the highly accurate all-electron full-potential linearized augmented plane wave (FLAPW) 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.
KW - density functional theory
KW - GaAs
KW - impact ionization
UR - http://www.scopus.com/inward/record.url?scp=85070980285&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85070980285&partnerID=8YFLogxK
U2 - 10.1023/A:1020728414482
DO - 10.1023/A:1020728414482
M3 - Article
AN - SCOPUS:85070980285
VL - 1
SP - 421
EP - 424
JO - Journal of Computational Electronics
JF - Journal of Computational Electronics
SN - 1569-8025
IS - 3
ER -