Electron and phonon temperature relaxation in semiconductors excited by thermal pulse
Abstract
Electron and phonon transient temperatures are analyzed in the case of nondegenerate semiconductors. An analytical solution is obtained for rectangular laser pulse absorption. It is shown that thermal diffusion is the main energy relaxation mechanism in the phonon subsystem. The mechanism depends on the correlation between the sample length l and the electron cooling length lɛ in an electron subsystem. Energy relaxation occurs by means of the electron thermal diffusion in thin samples (l≪lɛ), and by means of the electron-phonon energy interaction in thick samples (l≫lɛ). Characteristic relaxation times are obtained for all the cases, and analysis of these times is made. Electron and phonon temperature distributions in short and long samples are qualitatively and quantitatively analyzed for different correlations between the laser pulse duration and characteristic times.
- Publication:
-
Journal of Applied Physics
- Pub Date:
- January 2002
- DOI:
- 10.1063/1.1424057
- arXiv:
- arXiv:cond-mat/0202540
- Bibcode:
- 2002JAP....91..183G
- Keywords:
-
- 66.70.+f;
- 72.20.Jv;
- 72.20.Ht;
- 63.20.Kr;
- 71.38.-k;
- 72.40.+w;
- 61.80.Ba;
- 61.82.Fk;
- Nonelectronic thermal conduction and heat-pulse propagation in solids;
- thermal waves;
- Charge carriers: generation recombination lifetime and trapping;
- High-field and nonlinear effects;
- Phonon-electron and phonon-phonon interactions;
- Polarons and electron-phonon interactions;
- Photoconduction and photovoltaic effects;
- Ultraviolet visible and infrared radiation effects;
- Semiconductors;
- Condensed Matter
- E-Print:
- 33 pages, 16 figures