Electron-phonon interaction and scattering in Si and Ge: Implications for phonon engineering

Abstract

We report ab-initio results for electron-phonon (e-ph) coupling and display the existence of a large variation in the coupling parameter as a function of electron and phonon dispersion. This variation is observed for all phonon modes in Si and Ge, and we show this for representative cases where the initial electron states are at the band gap edges. Using these e-ph matrix elements, which include all possible phonon modes and electron bands within a relevant energy range, we evaluate the imaginary part of the electron self-energy in order to obtain the associated scattering rates. The temperature dependence is seen through calculations of the scattering rates at 0 K and 300 K. The results provide a basis for understanding the impacts of phonon scattering vs. orientation and geometry in the design of devices, and in analysis of transport phenomena. This provides an additional tool for engineering the transfer of energy from carriers to the lattice.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jul 28, 2015
Source ID
10.1063/1.4927530

Entities

People

  • John D. Albrecht
  • L. R. Ram-mohan
  • Nandan Tandon

Organizations

  • Air Force Research Laboratory
  • Defense Advanced Research Projects Agency
  • Michigan State University
  • Office of Naval Research
  • Worcester Polytechnic Institute

Tags

Fields of Study

  • Physics

Readers

  • Calculus or Mathematical Analysis
  • Quantum Chemistry
  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.

Technology Areas

  • Microelectronics
  • Microelectronics - Graphene