Chapter 4
Spin Relaxation

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Once the subband wave functions are evaluated, one can proceed further to calculate the surface roughness SR induced spin relaxation matrix elements [129]. The UTB silicon films under consideration consist of a very thin conducting layer sandwiched between two oxide layers. Thus, significant parts of the spin transport are carried along the oxide/silicon interfaces and the transport becomes very sensitive to the interface roughness. Therefore, the SR induced scattering plays an important role in UTB films and must be accounted for in spin relaxation calculations.

 4.1 Spin Relaxation Matrix Elements
 4.2 Spin Hot Spots and Spin Precession
  4.2.1 Spin Expectation Value
  4.2.2 Spin Precession
 4.3 Calculation of the Spin Relaxation Rates
  4.3.1 Surface Roughness Limited Spin Relaxation Rates
  4.3.2 Phonons
  4.3.3 Intravalley and g-Intervalley Relaxation Processes Rates
 4.4 Spin Lifetime Simulations
  4.4.1 Spin Lifetime Enhancement with Shear Strain
  4.4.2 Inter- and Intrasubband Components
  4.4.3 Effect of Spin Injection Orientation
 4.5 Momentum Relaxation Time Simulations
  4.5.1 Momentum Scattering Matrix Elements
  4.5.2 Calculation of the Momentum Relaxation Rates
 4.6 Valley Splitting in Unstrained Films
  4.6.1 Spin Relaxation Matrix Elements
  4.6.2 Spin Lifetime Calculations
 4.7 Primed Subbands and f-Processes
  4.7.1 Primed k p Hamiltonian
  4.7.2 Optical Phonon Limited Spin Relaxation Rate
  4.7.3 Optical Phonons in Spin Lifetime