Scientific Reports

Probing and driving of spin and charge states in double quantum dot under the quench

N. S. Maslova, P. I. Arseyev, Vladimir N. Mantsevich

Published Feb 28, 2019• 9 citations

Abstract

We have analyzed theoretically quenched dynamics of correlated double quantum dot (DQD) due to the switching "on" and "off" coupling to reservoirs. The possibility for controllable manipulation of charge and spin states in the double quantum dot was revealed and discussed. The proposed experimental scheme allows to prepare in DQD maximally entangled pure triplet state and to drive it to another entangled singlet state by tuning both applied bias and gate voltage. It was also demonstrated that the symmetry properties of the total system (double quantum dot coupled to electron reservoirs) allow to resolve the initially prepared two-electron states by detecting non-stationary spin-polarized currents flowing in both reservoirs and controlling the residual charge.

DOI: 10.1038/s41598-019-40038-2

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