- Turkish Journal of Physics
- Vol: 23 Issue: 4
- Electron Transport in GaAs Quantum Wells: Effect of Interface Roughness Scatterin
Electron Transport in GaAs Quantum Wells: Effect of Interface Roughness Scatterin
Authors : Rita Gupta
Pages : 551-558
View : 6 | Download : 4
Publication Date : 9999-12-31
Article Type : Makaleler
Abstract :The importance of interface roughness (IFR) scattering of electrons and LO-phonons for electron transport in semiconductor quantum wells is discussed. Modulation doping of quantum wells minimizes the effect of impurity scattering on the low-field electron mobility so that IFR scattering of electrons in the well becomes the major limiting factor. A model calculation of IFR scattering of electrons in quantum wells is presented and it is shown that (both)L and D, the parameters defining IFR, can be estimated by comparing the theoretical and experimental electron mobilities. The application of high electric field leads to a distribution of hot electrons which relax their energy and momentum through the emission of LO phonons. The dynamics of this non-equilibrium distribution of LO phonons greatly influences the electron transport at high fields. For example, a rapid momentum relaxation of hot LO phonons can lead to the saturation of electron drift velocity at high electric fields. Various mechanisms for momentum relaxation of LO phonons are presented and it is shown that IFR scattering is a major contributor to the non-drift of hot phonons. Implications for high-field electron transport in GaAs/AlGaAs quantum wells are discussed.Keywords : Turk. J. Phys., 23, (1999), 551-558. Full text: pdf Other articles published in the same issue: Turk. J. Phys., vol.23, iss.4.