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Driven dissipative dynamics of spins in quantum dots

Frederico Brito·Harry Westfahl Jr.·Amir O. Caldeira·Gilberto Medeiros-Ribeiro
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Abstract

We have studied the dissipative dynamics of a driven electronic spin trapped in a quantum dot. We consider the dissipative mechanism as due to the indirect coupling of the electronic spin to acoustic phonons via the spin-orbit/electron-phonon couplings. Using an effective spectral function of the dissipative phonon bath, we evaluated the expectation values of the spin components through the Bloch-Redfield theory. We show that due to a sharp bath resonance present in the effective spectral function, with typical energy much smaller than the electronic confinement energy, the dissipative spin has a rich dynamical behavior that helps us to determine some features of the spin-bath coupling. We also quantify the effects produced by the sharp bath resonance, and thus indicate the best regimes of operation in order to achieve the longest relaxation times for the spin.

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Frederico Brito, Harry Westfahl Jr., Amir O. Caldeira, Gilberto Medeiros-Ribeiro. 2007-03-01. Driven dissipative dynamics of spins in quantum dots. https://arxiv.org/abs/cond-mat/0703009

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