Impurities

Spin lifetimes for donors in Si

Objective:

  • Spin life-time (T1 times) measurements have been performed for single donors and STM-patterned donor clusters.
  • Previous theories use deformation potential constants to treat this problem.
  • Need a comprehensive approach to capture phonon induced T1 times quantitatively and qualitatively without adjustable parameters.

Method:

  • Electron-phonon Hamiltonian is represented by the full tight-binding electron Hamiltonian with strain.
  • Fermi’s Golden rule for relaxation rate.
  • Self consistent mean-field method for clusters with more than one electron.

Results/Impact:

  • Good quantitative and qualitative match with the measured T1 times for single donors .
  • Explains the donor cluster experimental results.
  • Predicts long T1 times with 1 electron-few donors clusters.

Group member involved: