Spin-Singlet–Spin-Triplet Transitions in Quantum Dots

Institute of Solid State Physics, Russian Academy of Sciences, Moskva, Moscow, Russia
Journal of Superconductivity 01/2003; 16(2):387-390. DOI: 10.1023/A:1023698310959

ABSTRACT We calculate the rate of the spin-singlet–spin-triplet (ST) relaxation in the two-electron droplet in a magnetic field. Far from the ST crossing point the rate turns out to be rather significant. In connection with the source-drain transport experiments, we consider this result is an explanation of the observed disappearance of the singlet (upper) level at magnetic fields, which are stronger than the ST crossing value.

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