Electrical control of singlet-triplet entanglement in lateral quantum dot molecules

Fanyao Qu; Iório, G. L.; Lopez-Richard, V.; Marques, G. E.
August 2009
Applied Physics Letters;8/24/2009, Vol. 95 Issue 8, p083101
Academic Journal
We study effects of spin-orbit coupling and electron-electron correlation, which can be electrically tuned, on the singlet-triplet entanglement in double lateral quantum dots charged with two electrons. We have found that the magnetic character of a double-dot system can be changed from diamagnetic to paramagnetic, only by adjusting the strength of spin-orbit coupling. Coulomb interaction leads to an unusual singlet-triplet energy splitting, accompanied by a shift of this transition energy to the lower magnetic field side in the energy spectrum.


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