3 research outputs found
Time evolution of an entangled initial state in coupled quantum dots with Coulomb correlations
We analyzed the dynamics of the initial singlet electronic state in the two
interacting single-level quantum dots (QDs) with Coulomb correlations, weakly
tunnel coupled to an electronic reservoir. We obtained correlation functions of
all orders for the electrons in the QDs by decoupling high-order correlations
between localized and band electrons in the reservoir. We proved that for
arbitrary mixed state the concurrence and entanglement can be determined from
the average value of particular combinations of electron's pair correlation
functions. Analysis of the pair correlation functions time evolution allows to
follow the changes of concurrence and entanglement during the relaxation
processes. We investigated the dependence of concurrence on the value of
Coulomb interaction and the energy levels spacing and found it's non-monotonic
behavior in the non-resonant case. We also demonstrated that the behavior of
pair correlation functions for two-electron entangled state in coupled QDs
points to the fulfillment of the Hund's rule for the strong Coulomb
interaction. We revealed the appearance of dynamical inverse occupation of the
QDs energy levels during the relaxation processes. Our results open up further
perspectives in solid state quantum information based on the controllable
dynamics of the entangled electronic states.Comment: 9 pages, 6 figure