We present a detailed experimental and theoretical analysis of the spin dynamics of two-dimensional electron gases (2DEGs) in a series of n -doped GaAs Alx Ga1-x As quantum wells. Picosecond-resolution polarized pump-probe reflection techniques were applied in order to study in detail the temperature, concentration, and quantum-well-width dependencies of the spin relaxation rate of a small photoexcited electron population. A rapid enhancement of the spin lifetime with temperature up to a maximum near the Fermi temperature of the 2DEG was demonstrated experimentally. These observations are consistent with the D'yakonov-Perel' spin-relaxation mechanism controlled by electron-electron collisions. The experimental results and theoretical predictions for the spin relaxation times are in good quantitative agreement.

Original languageEnglish
Article number165309
JournalPhysical Review B - Condensed Matter and Materials Physics
Volume75
Issue number16
DOIs
StatePublished - 10 Apr 2007

    Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

ID: 36468298