Electron transport in n-doped Si/SiGe quantum cascade structures

Lazic, I.; Ikonic, Z.; Milanovic, V.; Kelsall, R.W.; Indjin, D.; Harrison, P.

doi:doi:10.1063/1.2722244

Electron transport in n-doped Si/SiGe quantum cascade structures

Title

Electron transport in n-doped Si/SiGe quantum cascade structures

Author

Lazic, I.
Ikonic, Z.
Milanovic, V.
Kelsall, R.W.
Indjin, D.
Harrison, P.

Faculty

Applied Sciences

Department

Kavli Institute of Nanoscience

Date

2007-05-02

Abstract

An electron transport model in n-Si/SiGe quantum cascade or superlattice structures is described. The model uses the electronic structure calculated within the effective-mass complex-energy framework, separately for perpendicular (Xz) and in-plane (Xxy) valleys, the degeneracy of which is lifted by strain, and additionally by size quantization. The transport is then described via scattering between quantized states, using a rate equations approach and tight-binding expansion, taking the coupling with two nearest-neighbor periods. Acoustic phonon, optical phonon, alloy disorder, and interface roughness scattering are taken into account. The calculated current/voltage dependence and gain profiles are presented for two simple superlattice structures.

Subject

silicon
quantum cascade lasers
elemental semiconductors
Ge-Si alloys
semiconductor materials
semiconductor superlattices
band structure
effective mass
tight-binding calculations
phonons, interface roughness