arXiv subjects

Frederico V. Prudente

Publications and source records attributed to Frederico V. Prudente.

6 recordsLinked to original sources

arXiv2024

Electron Confinement study in a double quantum dot by means of Shannon Entropy Information

In this work, we use the Shannon informational entropies to study an electron confined in a double quantum dot; we mean the entropy in the space of positions, $S_r$, in the space of momentum, $S_p$, and the total entropy, $S_t = S_r+S_p$. We obtain $S_r$, $S_p$ and $S_t$ as a function of the parameters $A_2$ and $k$ which rules the height and the width, respectively, of the internal barrier of the confinement potential. We conjecture that the entropy $S_r$ maps the degeneracy of states when we vary $A_2$ and also is an indicator of the level of decoupling/coupling of the double quantum dot. We study the quantities $S_r$ and $S_p$ as measures of delocalization/localization of the probability distribution. Furthermore, we analyze the behaviors of the quantities $S_p$ and $S_t$ as a function of $A_2$ and $k$. Finally, we carried out an energy analysis and, when possible, compared our results with work published in the literature.

physics.atom-ph↗

arXiv2021

Coulomb Correlation and Information Entropies in Confined Helium-Like Atoms

The present work studies aspects of the electronic correlation in confined H$^{-}$, He and Li$^+$ atoms in their ground states using the informational entropies. In this way, different variational wavefunctions are employed in order of better take account of Coulomb correlation. The obtained values for the $S_r$, $S_p$ and $S_t$ entropies are sensitive in relation to Coulomb correlation effects. In the strong confinement regime, the effects of the Coulomb correlation are negligible and the employment of the models of independent particle and two non-interacting electrons confined by a impenetrable spherical cage gains importance in this regime. Lastly, energy values are obtained in good agreement with the results available in the literature.

physics.atom-ph↗

arXiv2020

On the oscillating properties of a two-electron quantum dot in the presence of a magnetic field

We give a basic explanation for the oscillating properties of some physical quantities of a two-electron quantum dot in the presence of a static magnetic field. This behaviour was discussed in a previous work of ours [AM Maniero, {\it et al}. J. Phys. B: At. Mol. Opt. Phys. 53:185001, 2020] and was identified as a manifestation of the {\it de Haas-van Alphen} effect, originally observed in the framework of diamagnetism of metals in the 30's. We show that this behaviour is a consequence of different eigenstates of the system assuming, in a certain interval of the magnetic field, the condition of the lowest energy singlet and triplet states.

cond-mat.str-el↗

arXiv2020

Evaluating Bohm's quantum force in the scattering process by a classical potential

In this work, we show an application of the de Broglie-Bohm Quantum Theory of Motion (QTM) as a powerful tool for evaluating Bohm's quantum force in the scattering process of a Gaussian wavepacket by a classical Eckart potential. Our results show that in the absence of a classical potential, the system experiences quantum effects arising from an effective force, intrinsically related to the existence of the wavepacket itself. In contrast, in the scattering by the classical potential, it experiences a quantum force effect even in the absence of any classical force, reinforcing the fact that potentials can act without classical force fields. Thus, this application could be useful to introduce QTM, through the discussion of the concept of Bohm's quantum force, as a classroom working tool instead of merely an alternative interpretation of the quantum theory.

quant-ph↗

arXiv2019

Information and quantum theories: an analysis in one-dimensional systems

We pedagogically present the information theory as originally established, explaining its essential ideas and paying attention to the expression employed to measure the amount of information. Also we discussed relationships between information and quantum theories. In this context we determined the information entropies on position, $S_x$, and momentum, $S_p$, spaces, besides the entropy sum $S_t$. Here, we use the modified entropic expressions that are dimensionally consistent. We provide original explanations for the behaviors of the $S_x$, $S_p$ and $S_t$ values analyzing the probability densities and by means of the normalization constants and properties of Fourier transform. We validate the entropic uncertainty relation and inspect the standard deviation and information entropies as measures of quantum uncertainty. The systems of interest unidimensional one-article quantum systems in ground and excited states.

quant-ph↗

arXiv2017

Shannon entropy: a study of confined hydrogenic-like atoms

The Shannon entropy in the atomic, molecular and chemical physics context is presented by using as test cases the hydrogenic-like atoms $H_c$, ${He_c}^+$ and ${Li_c}^{2+}$ confined by an impenetrable spherical box. Novel expressions for entropic uncertainty relation and Shannon entropies $S_r$ and $S_p$ are proposed to ensure their physical dimensionless characteristic. The electronic ground state energy and the quantities $S_r$, $S_p$ and $S_t$ are calculated for the hydrogenic-like atoms to different confinement radii by using a variational method. The global behavior of these quantities and different conjectures are analyzed. The results are compared, when available, with those previously published.

physics.atom-ph↗