arXiv subjects

Andre A. Marinho

Publications and source records attributed to Andre A. Marinho.

8 recordsLinked to original sources

arXiv2025

Intermediate statistics: addressing the Landau diamagnetism problem

Quantum groups and quantum algebras have received considerable attention in the last decades because they are very useful as mathematical tools of research. Existing proposals for quantum groups have always suggested the idea of deforming a classical object. Motivated by the possibility of anyons in three dimensions ($d=3$), with important consequences to a wide range of fields of physics, in the present work we investigate how the magnetization and other thermodynamic quantities, associated to the Landau diamagnetism problem, depend on the deforming parameter of two models with intermediate statistics: (i) $q$-fermions and (ii) $F$-anyons, and make {\it comparisons between both cases}. In particular, we extend the results from the literature for $q$-fermions by considering {\it second order terms} in the expansion of the grand partition function. Also, we find that for $F$-anyons statistics the magnetization shows a stronger response with respect to magnetic fields compared to magnetization for $q$-fermions statistics. This theoretical outcome may be experimentally verified for instance in superconductors, that are perfect diamagnetic materials with strong magnetic susceptibility, by adjusting impurities or pressure. The latter can be associated to the deforming parameter $q$.

cond-mat.stat-mech↗

arXiv2024

Intermediate statistics: addressing the thermoelectric properties of solids

We study the thermodynamics of a crystalline solid by applying intermediate statistics obtained by deforming known solid state models using the mathematics of $q$-analogs. We apply the resulting $q$-deformation to both the Einstein and Debye models and study the deformed thermal and electrical conductivities and the deformed Debye specific heat. We find that the $q$-deformation acts in two different ways -- but not necessarily as independent mechanisms. First, it acts as an effective factor of disorder or impurity, modifying the characteristics of a crystalline structure, which are phenomena described by q-bosons. Second, it also manifests intermediate statistics, namely, the B-anyons (or B-type systems). For the latter case, we have identified the Schottky effect, normally associated with high-$T_c$ superconductors in the presence of rare-earth-ion impurities. We also find that it increases the specific heat of the solids beyond the Dulong-Petit limit at high temperature. Such an effect is usually related to anharmonicity of interatomic interactions. Alternatively, since in the $q$-bosons case the statistics are in principle maintained, the effect of the deformation acts more slowly due to a small change in the crystal lattice. On the other hand, B-anyons that belong to modified statistics are more sensitive to the deformation. The results reported here may be verified experimentally, for instance, in experimental samples by inserting impurities, or changes in pressure or temperature if one assumes these tuning quantities are related with the q-deformation parameter.

cond-mat.stat-mech↗

arXiv2020

The connection between Jackson and Hausdorff derivatives in the context of generalized statistical mechanics

In literature one can find many generalizations of the usual Leibniz derivative, such as Jackson derivative, Tsallis derivative and Hausdorff derivative. In this article we present a connection between Jackson derivative and recently proposed Hausdorff derivative. On one hand, the Hausdorff derivative has been previously associated with non-extensivity in systems presenting fractal aspects. On the other hand, the Jackson derivative has a solid mathematical basis because it is the $\overline{q}$-analog of the ordinary derivative and it also arises in quantum calculus. From a quantum deformed $\overline{q}$-algebra we obtain the Jackson derivative and then address the problem of $N$ non-interacting quantum oscillators. We perform an expansion in the quantum grand partition function from which we obtain a relationship between the parameter $\overline{q}$, related to Jackson derivative, and the parameters $ζ$ and $q$ related to Hausdorff derivative and Tsallis derivative, respectively.

cond-mat.stat-mech↗

arXiv2019

Thermoelectric Properties of BiSbTe Alloy Nanofilms Produced by DC Sputtering: Experiments and Modeling

Thermoelectricity refers to the conversion of thermal energy into electrical energy and vice-versa, which relies on three main effects: Seebeck, Peltier and Thomson, all of which are manifestations of heat and electricity flow. In this work we investigate the deposition of nanometric films and the effect of a thermal treatment on their thermoelectric properties. The films are based on BiSbT e ternary alloys, obtained by deposition on a substrate using the DC sputtering technique. We produced sputtering targets with repurposed materials from commercial thermoelectric modules. In this way, we explore an environmentally responsible destination for discarded devices, with in situ preparation and manufacture of film-based thermoelectric modules. Film samples show an improvement trend in thermoelectric efficiency as the annealing temperature is increased in the range 423-623 K. The experimental data regarding thermal conductivity, electrical resistivity (or electrical conductivity), and the Seebeck coefficient were analyzed with the theory of q-deformed algebra. Applying a q-deformation to our system we can model the effect of the annealing temperature on the thermal and electrical conductivities, as well as the Seebeck coefficient, and argue that the q-factor must be related to structural properties of the films. We believe that our work could pave the way for future developments in the modeling of experimental measurements via the formalism of q-deformation algebra.

physics.app-ph↗

arXiv2019

Hybrid deformed algebra

By considering $p,q$-deformed and $μ$-deformed algebras we propose an association of them to form a hybrid deformed algebra. The increased number of available parameters can provide us with a richer tool to investigate new scenarios within hybrid deformed statistics.

cond-mat.stat-mech↗

arXiv2018

Hermite polynomials and Fibonacci Oscillators

We compute the ($q_1,q_2$)-deformed Hermite polynomials by replacing the quantum harmonic oscillator problem to Fibonacci oscillators. We do this by applying the ($q_1, q_2$)-extension of Jackson derivative. The deformed energy spectrum is also found in terms of these parameters. We conclude that the deformation is more effective in higher excited states. We conjecture that this achievement may find applications in the inclusion of disorder and impurity in quantum systems. The ordinary quantum mechanics is easily recovered as $q_1 = 1$ and $q_2\to1$ or vice versa.

cond-mat.stat-mech↗

arXiv2015

Thermal and electrical properties of a solid through Fibonacci oscillators

We investigate the thermodynamics of a crystalline solid applying q-deformed algebra of Fibonacci oscillators through the generalized Fibonacci sequence of two real and independent deformation parameters q1 and q2. We based part of our study on both Einstein and Debye models, exploring primarily (q1,q2)-deformed thermal and electric conductivities as a function of Debye specific heat. The results revealed that q-deformation acts as a factor of disorder or impurity, modifying the characteristics of a crystalline structure. Specially, one may find the possibility of adjusting the Fibonacci oscillators to describe the change of thermal and electrical conductivities of a given element as one inserts impurities. Each parameter can be associated to different types of deformations such as disorders and impurities.

cond-mat.stat-mech↗

arXiv2014

Fibonacci Oscillators in the Landau Diamagnetism problem

We address the issue of the Landau diamagnetism problem via $q$-deformed algebra of Fibonacci oscillators through its generalized sequence of two real and independent deformation parameters $q_1$ and $q_2$. We obtain $q$-deformed thermodynamic quantities such as internal energy, number of particles, magnetization and magnetic susceptibility which recover their usual form in the degenerate limit $q_1^2 + q_2^2$=1.

cond-mat.stat-mech↗