Physical Review A

Time evolution of entangled Bell states in coupled quantum dots in the presence of fluctuations

N. S. Maslova, Vladimir N. Mantsevich, Igor Michailovitsch Sokolov, P. I. Arseyev

Published Mar 25, 2024• 1 citation

Abstract

We analyze the dynamics of two-qubit entangled Bell states in coupled quantum dots (QDs) in the presence of both fluctuations and coherent electron hopping between the dots. The explicit expression for time-dependent probability to find the system in the different Bell states was obtained for various initial conditions by means of Keldysh diagram technique. It was revealed that time evolution of one pair of Bell states and its decay rate strongly differs from another one. It was demonstrated that one pair of Bell states is more robust against fluctuations than another one. The stationary occupation of Bell states for different initial conditions was also analyzed. Obtained results are important for the problems where long-living Bell states are needed such as the security of quantum communication and quantum information processing.

DOI: 10.1103/physreva.109.032430

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