Spin relaxation in silicon coupled quantum dots

We present a detailed investigation for spin relaxation processes in silicon coupled quantum dots. Low-field magnetoconductance measurements have been employed to deduce phase dephasing and spin relaxation rates. On the basis of the dephasing theory containing triplet channel interaction, we have demonstrated that small energy transfer scattering process is the dominant dephasing mechanism, and strong electron-electron interaction results in an interdot spin-exchange relaxation process. Triplet-singlet relaxation is found to be another important spin relaxation process in the inner quantum dots, taking into account the triplet-singlet splitting induced by spin-orbit coupling. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3167817]