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arXiv · 1605.01642

Relaxation of Ferroelectric States in 2D Distributions of quantum Dots:EELS Simulation

C. M. Cortés·L. Meza-Montes·R. E. Moctezuma·J. L. Carrillo
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Abstract

The relaxation time of collective electronic states in a 2D distribution of quantum dots is investigated theoretically by simulating EELS experiments. From the numerical calculation of the probability of energy loss of an electron beam, traveling parallel to the distribution, it is possible to estimate the damping time of ferroelectric-like states. We generate this collective response of the distribution by introducing a mean field interaction among the quantum dots, and then, the model is extended incorporating effects of long-range correlations through a Bragg-Williams approximation. The behavior of the dielectric function, the energy loss function, and the relaxation time of ferroelectric-like states is then investigated as a function of the temperature of the distribution and the damping constant of the electronic states in the single quantum dots. The robustness of the trends and tendencies of our results indicate that this scheme of analysis can guide experimentalists to develop tailored quantum dots distributions for specific applications.

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C. M. Cortés, L. Meza-Montes, R. E. Moctezuma, J. L. Carrillo. 2016-05-05. Relaxation of Ferroelectric States in 2D Distributions of quantum Dots:EELS Simulation. https://doi.org/10.1088/0022-3727%2F49%2F25%2F255304

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