Spin Relaxation in Isotopically Purified Silicon Quantum Dots

We investigate spin-flip processes of Si quantum dots due to spin-orbit coupling. We utilize the spin-orbit coupling constants related to bulk and structure inversion asymmetry obtained numerically for two dimensional heterostructures. We find that the spin-flip rate is very sensitive to these coupling constants. We investigate the nuclei-mediated spin-flip process and find the level of the isotope $^{29}$Si concentration for which this mechanism become dominant.