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Related papers: Spin-waves in a complex magnetic system: nonextens…

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During the past few years, nonextensive statistics has been successfully applied to explain many different kinds of systems. Through these studies some interpretations of the entropic parameter q, which has major role in this statistics, in…

Statistical Mechanics · Physics 2011-07-01 D. O. Soares-Pinto , M. S. Reis , R. S. Sarthour , I. S. Oliveira

In this paper we present a thorough analysis of two systems magnetically inhomogeneous: the manganite La$_{0.7}$Sr$_{0.3}$MnO$_3$/MgO and the amorphous alloy Cu$_{90}$Co$_{10}$. In both cases, the non-extensive statistics yield a faithful…

Statistical Mechanics · Physics 2009-11-11 M. S. Reis , V. S. Amaral , R. S. Sarthour , I. S. Oliveira

Statistical mechanics can only be ultimately justified in terms of microscopic dynamics (classical, quantum, relativistic, or any other). It is known that Boltzmann-Gibbs statistics is based on the hypothesis of exponential sensitivity to…

Statistical Mechanics · Physics 2009-11-10 Constantino Tsallis

We analyzed the magnetic behavior of a S-spin system within framework of the Tsallis nonextensive statistics, employing the normalized approach. Unusual properties on magnetization, entropy and susceptibility emerge, as a consequence of…

Statistical Mechanics · Physics 2009-11-07 M. S. Reis , J. P. Araujo , V. S. Amaral , E. K. Lenzi , I. S. Oliveira

We argue that contrary to recent suggestions, non-extensive statistical mechanics has no relevance for inhomogeneous systems of particles interacting by short-range potentials. We show that these systems are perfectly well described by the…

Statistical Mechanics · Physics 2014-09-12 Matheus Girotto , Alexandre P. dos Santos , Renato Pakter , Yan Levin

We present a general theoretical approach for the quantitative description of parametric excitation of spin-wave modes in confined micromagnetic systems. This type of problem belongs to a broader class of nonlinear modal dynamics that arise…

Mesoscale and Nanoscale Physics · Physics 2026-01-13 Massimiliano d'Aquino , Salvatore Perna , Hugo Merbouche , Grégoire De Loubens

The critique against using Boltzmann's microcanonical entropy, an "ensemble measure", as foundation of statistics is rebuffed. The confusion of the microcanonical distribution with the exponential Boltzmann-Gibbs (``BG'') distribution is…

Statistical Mechanics · Physics 2007-05-23 D. H. E. Gross

The parametric excitation of spin waves by coherent surface acoustic waves is demonstrated experimentally in metallic magnetic thin film structures. The involved magnon modes are analyzed with micro-focused Brillouin light scattering…

Boltzmann-Gibbs statistical mechanics is based on the entropy $S_{BG}=-k \sum_{i=1}^W p_i \ln p_i$. It enables a successful thermal approach of ubiquitous systems, such as those involving short-range interactions, markovian processes, and,…

Statistical Mechanics · Physics 2009-11-10 Constantino Tsallis , Edgardo Brigatti

In the present paper we make a thorough analysis of a classical spin system, within the framework of Tsallis nonextensive statistics. From the analysis of the generalized Gibbs free energy, within the mean-field approximation, a…

Statistical Mechanics · Physics 2009-11-10 M. S. Reis , J. P. Araujo , V. S. Amaral , I. S. Oliveira

High-energy phenomena presenting strong dynamical correlations, long-range interactions and microscopic memory effects are well described by nonextensive versions of the canonical Boltzmann-Gibbs statistical mechanics. After a brief…

High Energy Physics - Lattice · Physics 2014-05-30 Rafael B. Frigori

We introduce a novel approach for the investigation of spin-wave excitations in itinerant ferromagnets. Our theory is based on a variational treatment of general multi-band Hubbard models which describe elements and compounds of transition…

Strongly Correlated Electrons · Physics 2009-10-31 J. Buenemann

In this paper a composed A+B magnetic system, with spins J_A=2 and J_B=3/2, is considered within the mean-field approximation, in the framework of Tsallis nonextensive statistics. Our motivation is twofold: (1) to approach the existing…

Statistical Mechanics · Physics 2009-09-24 F. A. R. Navarro , M. S. Reis , E. K Lenzi , I. S. Olivera

Controlling magnon densities in magnetic materials enables driving spin transport in magnonic devices. We demonstrate the creation of large, out-of-equilibrium magnon densities in a thin-film magnetic insulator via microwave excitation of…

Nonlinear interactions are crucial in science and engineering. Here, we investigate wave interactions in a highly nonlinear magnetic system driven by parametric pumping leading to Bose--Einstein condensation of spin-wave quanta -- magnons.…

The non-extensive statistical mechanics has been applied to describe a variety of complex systems with inherent correlations and feedback loops. Here we present a dynamical model based on previously proposed static model exhibiting in the…

Statistical Mechanics · Physics 2016-04-20 A. Kononovicius , J. Ruseckas

A mutilated model is constructed to approximate the collision term of spin Boltzmann equation that incorporates newly appearing collisional invariants i.e, the total angular momentum. With recourse to degenerate perturbation theory, the…

High Energy Physics - Phenomenology · Physics 2023-01-23 Jin Hu , Zhe Xu

A statistical thermodynamic approach of moving particles forming an elastic body is presented which leads to reveal molecular-mechanical properties of classical and nonextensive dynamical systems. We derive the Boltzmann-Gibbs (BG) entropy…

Statistical Mechanics · Physics 2009-11-10 Enrique Canessa

Nonrelativistic systems exhibiting collective magnetic behavior are analyzed in the framework of effective Lagrangians. The method, formulating the dynamics in terms of Goldstone bosons, allows to investigate the consequences of spontaneous…

Condensed Matter · Physics 2009-10-31 Christoph P. Hofmann

The properties of the nonextensive parameter q and the Tsallis distribution for self-gravitating systems are studied. A mathematical expression of q is deduced based on the generalized Boltzmann equation, the q-H theorem and the generalized…

Statistical Mechanics · Physics 2015-08-10 Jiulin Du
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