Stability and decoherence of optical bipolaron in symmetric quantum dot
Unité de Recherche de Matière Condensée, d′Electronique et de Traitement de Signal (UR-MACETS), Department of Physics, Faculty of Science, University of Dschang, P. O. Box: 67, Dschang, Cameroon
Accepted: 5 October 2020
Published online: 16 October 2020
Optical bipolaron’s stability and decoherence confined in the symmetric quantum dot are investigated utilizing the modified Lee, Low, and Pines variational method. The binding energy of optical bipolaron in symmetrical quantum dot systems is obtained by computing the energy of the fundamental state, the energy of the ground state of the single polaron, and the prime state excited energy. The formation of the bipolaron in quantum dot structures is thus obtained. Optical bipolaron stability appears to be quite sensitive to the dimensionality of the quantum dot and the material, where α and η material parameters are considered. By investigating information processing, it is possible to compute Shannon’s entropy to study a qubit’s decoherence when in the superimposed state of the fundamental and the prime state excited. We see that decoherence time grows and shrinks with the dielectric constant and the dispersion coefficient. Thus, there exists a threshold dielectric constant and dispersion coefficient which maximizes decoherence time. This threshold dielectric constant and dispersion coefficient increases with the reduction in electron–phonon coupling. This study gives a guideline for the appropriate materials used in the construction of nanodevice.
© Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature 2020