1
|
Spasojević D, Marinković M, Jovković D, Janićević S, Laurson L, Djordjević A. Barkhausen noise in disordered striplike ferromagnets: Experiment versus simulations. Phys Rev E 2024; 109:024110. [PMID: 38491707 DOI: 10.1103/physreve.109.024110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/29/2024] [Indexed: 03/18/2024]
Abstract
In this work, we present a systematic comparison of the results obtained from the low-frequency Barkhausen noise recordings in nanocrystalline samples with those from the numerical simulations of the random-field Ising model systems. We performed measurements at room temperature on a field-driven metallic glass stripe made of VITROPERM 800 R, a nanocrystalline iron-based material with an excellent combination of soft and magnetic properties, making it a cutting-edge material for a wide range of applications. Given that the Barkhausen noise emissions emerging along a hysteresis curve are stochastic and depend in general on a variety of factors (such as distribution of disorder due to impurities or defects, varied size of crystal grains, type of domain structure, driving rate of the external magnetic field, sample shape and temperature, etc.), adequate theoretical modeling is essential for their interpretation and prediction. Here the Random field Ising model, specifically its athermal nonequilibrium version with the finite driving rate, stands out as an appropriate choice due to the material's nanocrystalline structure and high Curie temperature. We performed a systematic analysis of the signal properties and magnetization avalanches comparing the outcomes of the numerical model and experiments carried out in a two-decade-wide range of the external magnetic field driving rates. Our results reveal that with a suitable choice of parameters, a considerable match with the experimental results is achieved, indicating that this model can accurately describe the Barkhausen noise features in nanocrystalline samples.
Collapse
Affiliation(s)
- Djordje Spasojević
- Faculty of Physics, University of Belgrade, P. O. Box 44, 11001 Belgrade, Republic of Serbia
| | - Miloš Marinković
- Faculty of Physics, University of Belgrade, P. O. Box 44, 11001 Belgrade, Republic of Serbia
| | - Dragutin Jovković
- Faculty of Mining and Geology, University of Belgrade, P. O. Box 162, 11000 Belgrade, Republic of Serbia
| | - Sanja Janićević
- Faculty of Science, University of Kragujevac, P. O. Box 60, 34000 Kragujevac, Republic of Serbia
| | - Lasse Laurson
- Computational Physics Laboratory, Tampere University, P. O. Box 692, FI-33014 Tampere, Finland
| | - Antonije Djordjević
- School of Electrical Engineering, University of Belgrade, 11000 Belgrade, Republic of Serbia and Serbian Academy of Sciences and Arts, 11000 Belgrade, Republic of Serbia
| |
Collapse
|
2
|
Spasojević D, Graovac S, Janićević S. Interplay of disorder and type of driving in disordered ferromagnetic systems. Phys Rev E 2022; 106:044107. [PMID: 36397527 DOI: 10.1103/physreve.106.044107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 09/19/2022] [Indexed: 06/16/2023]
Abstract
We investigate the effects of adiabatic, quasistatic, and finite-rate types of driving on the evolution of disordered three-dimensional ferromagnetic systems, studied within the frame of the nonequilibrium athermal random field Ising model. The effects were examined in all three domains of disorder (low, high, and transitional) for all types of driving, and in a wide range of driving rates for quasistatic and finite-rate driving, providing an extensive overview and comparison of the joint effects that the disorder, type of driving, and rate regime have on the system's behavior.
Collapse
Affiliation(s)
- Djordje Spasojević
- Faculty of Physics, University of Belgrade, P.O. Box 44, 11001 Belgrade, Serbia
| | - Stefan Graovac
- Faculty of Physics, University of Belgrade, P.O. Box 44, 11001 Belgrade, Serbia
| | - Sanja Janićević
- Faculty of Science, University of Kragujevac, P.O. Box 60, 34000 Kragujevac, Serbia
| |
Collapse
|
3
|
Graovac S, Mijatović S, Spasojević D. Mechanism of subcritical avalanche propagation in three-dimensional disordered systems. Phys Rev E 2021; 103:062123. [PMID: 34271753 DOI: 10.1103/physreve.103.062123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Accepted: 05/25/2021] [Indexed: 11/07/2022]
Abstract
We present a numerical study on necessary conditions for the appearance of infinite avalanche below the critical point in disordered systems that evolve throughout metastable states. The representative of those systems is the nonequilibrium athermal random-field Ising model. We investigate the impact on propagation of infinite avalanche of both the interface of flipped spins at the avalanche's starting point and the number of independent islands of flipped spins in the system at the moment when the avalanche starts. To deduce what effects are originated due to finite system's size, and to distinguish them from the real necessary conditions for the appearance of the infinite avalanche, we examined lattices of different sizes as well as other key parameters for the avalanche propagation.
Collapse
Affiliation(s)
- Stefan Graovac
- Faculty of Physics, University of Belgrade, P.O. Box 44, 11001 Belgrade, Serbia
| | - Svetislav Mijatović
- Faculty of Physics, University of Belgrade, P.O. Box 44, 11001 Belgrade, Serbia
| | - Djordje Spasojević
- Faculty of Physics, University of Belgrade, P.O. Box 44, 11001 Belgrade, Serbia
| |
Collapse
|
4
|
Jovković D, Janićević S, Mijatović S, Laurson L, Spasojević D. Effects of external noise on threshold-induced correlations in ferromagnetic systems. Phys Rev E 2021; 103:062114. [PMID: 34271613 DOI: 10.1103/physreve.103.062114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 05/17/2021] [Indexed: 11/07/2022]
Abstract
In the present paper we investigate the impact of the external noise and detection threshold level on the simulation data for the systems that evolve through metastable states. As a representative model of such systems we chose the nonequilibrium athermal random-field Ising model with two types of the external noise, uniform white noise and Gaussian white noise with various different standard deviations, imposed on the original response signal obtained in model simulations. We applied a wide range of detection threshold levels in analysis of the signal and show how these quantities affect the values of exponent γ_{S/T} (describing the scaling of the average avalanche size with duration), the shift of waiting time between the avalanches, and finally the collapses of the waiting time distributions. The results are obtained via extensive numerical simulations on the equilateral three-dimensional cubic lattices of various sizes and disorders.
Collapse
Affiliation(s)
- Dragutin Jovković
- Faculty of Mining and Geology, University of Belgrade, P.O. Box 162, 11000 Belgrade, Serbia
| | - Sanja Janićević
- Faculty of Science, University of Kragujevac, P.O. Box 60, 34000 Kragujevac, Serbia
| | - Svetislav Mijatović
- Faculty of Physics, University of Belgrade, P.O. Box 44, 11001 Belgrade, Serbia
| | - Lasse Laurson
- Computational Physics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere, Finland
| | - Djordje Spasojević
- Faculty of Physics, University of Belgrade, P.O. Box 44, 11001 Belgrade, Serbia
| |
Collapse
|
5
|
Mijatović S, Jovković D, Spasojević D. Nonequilibrium athermal random-field Ising model on hexagonal lattices. Phys Rev E 2021; 103:032147. [PMID: 33862757 DOI: 10.1103/physreve.103.032147] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 03/08/2021] [Indexed: 11/07/2022]
Abstract
We present the results of a study providing numerical evidence for the absence of critical behavior of the nonequilibrium athermal random-field Ising model in adiabatic regime on the hexagonal two-dimensional lattice. The results are obtained on the systems containing up to 32768×32768 spins and are the averages of up to 1700 runs with different random-field configurations per each value of disorder. We analyzed regular systems as well as the systems with different preset conditions to capture behavior in thermodynamic limit. The superficial insight to the avalanche propagation in this type of lattice is given as a stimulus for further research on the topic of avalanche evolution. With obtained data we may conclude that there is no critical behavior of random-field Ising model on hexagonal lattice which is a result that differs from the ones found for the square and for the triangular lattices supporting the recent conjecture that the number of nearest neighbors affects the model criticality.
Collapse
Affiliation(s)
- Svetislav Mijatović
- Faculty of Physics, University of Belgrade, P.O.B. 44, 11001 Belgrade, Serbia
| | - Dragutin Jovković
- Faculty of Mining and Geology, University of Belgrade, P.O.B. 162, 11000 Belgrade, Serbia
| | - Djordje Spasojević
- Faculty of Physics, University of Belgrade, P.O.B. 44, 11001 Belgrade, Serbia
| |
Collapse
|
6
|
Mijatović S, Branković M, Graovac S, Spasojević D. Avalanche properties in striplike ferromagnetic systems. Phys Rev E 2020; 102:022124. [PMID: 32942372 DOI: 10.1103/physreve.102.022124] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Accepted: 07/24/2020] [Indexed: 11/07/2022]
Abstract
We present numerical findings on the behavior of the athermal nonequilibrium random-field Ising model of spins at the thin striplike L_{1}×L_{2}×L_{3} cubic lattices with L_{1}<L_{2}<L_{3}. Changing of system sizes highly influences the evolution and shape of avalanches. The smallest avalanches [classified as three-dimension- (3D) like] are unaffected by the system boundaries, the larger are sandwiched between the top and bottom system faces so are 2D-like, while the largest are extended over the system lateral cross section and propagate along the length L_{3} like in 1D systems. Such a structure of avalanches causes double power-law distributions of their size, duration, and energy with larger effective critical exponent corresponding to 3D-like and smaller to 2D-like avalanches. The distributions scale with thickness L_{1} and are collapsible following the proposed scaling predictions which, together with the distributions' shape, might be important for analysis of the Barkhausen noise experimental data for striplike samples. Finally, the impact of system size on external field that triggers the largest avalanche for a given disorder is presented and discussed.
Collapse
Affiliation(s)
- Svetislav Mijatović
- Faculty of Physics, University of Belgrade, P. O. Box 44, 11001 Belgrade, Serbia
| | - Milica Branković
- Faculty of Physics, University of Belgrade, P. O. Box 44, 11001 Belgrade, Serbia
| | - Stefan Graovac
- Faculty of Physics, University of Belgrade, P. O. Box 44, 11001 Belgrade, Serbia
| | - Djordje Spasojević
- Faculty of Physics, University of Belgrade, P. O. Box 44, 11001 Belgrade, Serbia
| |
Collapse
|
7
|
Zech P, Otto A, Radons G. Dynamics of a driven harmonic oscillator coupled to independent Ising spins in random fields. Phys Rev E 2020; 101:042217. [PMID: 32422826 DOI: 10.1103/physreve.101.042217] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 04/08/2020] [Indexed: 11/07/2022]
Abstract
We aim at an understanding of the dynamical properties of a periodically driven damped harmonic oscillator coupled to a Random Field Ising Model (RFIM) at zero temperature, which is capable of showing complex hysteresis. The system is a combination of a continuous (harmonic oscillator) and a discrete (RFIM) subsystem, which classifies it as a hybrid system. In this paper we focus on the hybrid nature of the system and consider only independent spins in quenched random local fields, which can already lead to complex dynamics such as chaos and multistability. We study the dynamic behavior of this system by using the theory of piecewise-smooth dynamical systems and discontinuity mappings. Specifically, we present bifurcation diagrams and Lyapunov exponents as well as results for the shape and the dimensions of the attractors and the self-averaging behavior of the attractor dimensions and the magnetization. Furthermore we investigate the dynamical behavior of the system for an increasing number of spins and the transition to the thermodynamic limit, where the system behaves like a driven harmonic oscillator with an additional nonlinear smooth external force.
Collapse
Affiliation(s)
- Paul Zech
- Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
| | - Andreas Otto
- Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
| | - Günter Radons
- Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
| |
Collapse
|
8
|
Mijatović S, Jovković D, Janićević S, Spasojević D. Critical disorder and critical magnetic field of the nonequilibrium athermal random-field Ising model in thin systems. Phys Rev E 2019; 100:032113. [PMID: 31639960 DOI: 10.1103/physreve.100.032113] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Indexed: 11/07/2022]
Abstract
In the present study of the nonequilibrium athermal random-field Ising model we focus on the behavior of the critical disorder R_{c}(l) and the critical magnetic field H_{c}(l) under different boundary conditions when the system thickness l varies. We propose expressions for R_{c}(l) and H_{c}(l) as well as for the effective critical disorder R_{c}^{eff}(l,L) and effective critical magnetic field H_{c}^{eff}(l,L) playing the role of the effective critical parameters for the L×L×l lattices of finite lateral size L. We support these expressions by the scaling collapses of the magnetization and susceptibility curves obtained in extensive simulations. The collapses are achieved with the two-dimensional (2D) exponents for l below some characteristic value, providing thus a numerical evidence that the thin systems exhibit a 2D-like criticality which should be relevant for the experimental analyses of thin ferromagnetic samples.
Collapse
Affiliation(s)
| | - Dragutin Jovković
- Faculty of Mining and Geology, University of Belgrade, POB 162, 11000 Belgrade, Serbia
| | - Sanja Janićević
- Faculty of Science, University of Kragujevac, POB 60, 34000 Kragujevac, Serbia
| | - Djordje Spasojević
- Faculty of Physics, University of Belgrade, POB 44, 11001 Belgrade, Serbia
| |
Collapse
|
9
|
Tadić B, Mijatović S, Janićević S, Spasojević D, Rodgers GJ. The critical Barkhausen avalanches in thin random-field ferromagnets with an open boundary. Sci Rep 2019; 9:6340. [PMID: 31004121 PMCID: PMC6474887 DOI: 10.1038/s41598-019-42802-w] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 04/04/2019] [Indexed: 11/10/2022] Open
Abstract
The interplay between the critical fluctuations and the sample geometry is investigated numerically using thin random-field ferromagnets exhibiting the field-driven magnetisation reversal on the hysteresis loop. The system is studied along the theoretical critical line in the plane of random-field disorder and thickness. The thickness is varied to consider samples of various geometry between a two-dimensional plane and a complete three-dimensional lattice with an open boundary in the direction of the growing thickness. We perform a multi-fractal analysis of the Barkhausen noise signals and scaling of the critical avalanches of the domain wall motion. Our results reveal that, for sufficiently small thickness, the sample geometry profoundly affects the dynamics by modifying the spectral segments that represent small fluctuations and promoting the time-scale dependent multi-fractality. Meanwhile, the avalanche distributions display two distinct power-law regions, in contrast to those in the two-dimensional limit, and the average avalanche shapes are asymmetric. With increasing thickness, the scaling characteristics and the multi-fractal spectrum in thicker samples gradually approach the hysteresis loop criticality in three-dimensional systems. Thin ferromagnetic films are growing in importance technologically, and our results illustrate some new features of the domain wall dynamics induced by magnetisation reversal in these systems.
Collapse
Affiliation(s)
- Bosiljka Tadić
- Department for Theoretical Physics, Jožef Stefan Institute, P.O. Box 3000, SI-1001, Ljubljana, Slovenia. .,Complexity Science Hub, Vienna, Austria.
| | - Svetislav Mijatović
- Faculty of Physics, University of Belgrade, POB 368, 11001, Belgrade, Serbia
| | - Sanja Janićević
- Faculty of Physics, University of Belgrade, POB 368, 11001, Belgrade, Serbia
| | - Djordje Spasojević
- Faculty of Physics, University of Belgrade, POB 368, 11001, Belgrade, Serbia
| | | |
Collapse
|
10
|
Janićević S, Mijatović S, Spasojević D. Critical behavior of the two-dimensional nonequilibrium zero-temperature random field Ising model on a triangular lattice. Phys Rev E 2017; 95:042131. [PMID: 28505865 DOI: 10.1103/physreve.95.042131] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Indexed: 06/07/2023]
Abstract
We present a numerical study of the critical behavior of the nonequilibrium zero-temperature random field Ising model in two dimensions on a triangular lattice. Our findings, based on the scaling analysis and collapse of data collected in extensive simulations of systems with linear sizes up to L=65536, show that the model is in a different universality class than the same model on a quadratic lattice, which is relevant for a better understanding of model universality and the analysis of experimental data.
Collapse
Affiliation(s)
- Sanja Janićević
- Faculty of Physics, University of Belgrade, P.O. Box 368, 11001 Belgrade, Serbia
| | - Svetislav Mijatović
- Faculty of Physics, University of Belgrade, P.O. Box 368, 11001 Belgrade, Serbia
| | - Djordje Spasojević
- Faculty of Physics, University of Belgrade, P.O. Box 368, 11001 Belgrade, Serbia
| |
Collapse
|
11
|
Navas-Portella V, Vives E. Influence of the aspect ratio and boundary conditions on universal finite-size scaling functions in the athermal metastable two-dimensional random field Ising model. Phys Rev E 2016; 93:022129. [PMID: 26986310 DOI: 10.1103/physreve.93.022129] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Indexed: 11/07/2022]
Abstract
This work studies universal finite size scaling functions for the number of one-dimensional spanning avalanches in a two-dimensional (2D) disordered system with boundary conditions of different nature and different aspect ratios. To this end, we will consider the 2D random field Ising model at T=0 driven by the external field H with athermal dynamics implemented with periodic and forced boundary conditions. We have chosen a convenient scaling variable z that accounts for the deformation of the distance to the critical point caused by the aspect ratio. In addition, assuming that the dependence of the finite size scaling functions on the aspect ratio can be accounted for by an additional multiplicative factor, we have been able to collapse data for different system sizes, different aspect ratios, and different types of the boundary conditions into a single scaling function Q̂.
Collapse
Affiliation(s)
- Víctor Navas-Portella
- Departament d'Estructura i Constituents de la Matèria, Facultat de Física, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Catalonia, Spain.,Centre de Recerca Matemàtica, Edifici C, Campus Bellaterra, E-08193 Bellaterra, Catalonia, Spain
| | - Eduard Vives
- Departament d'Estructura i Constituents de la Matèria, Facultat de Física, Universitat de Barcelona, Diagonal 645, 08028 Barcelona, Catalonia, Spain
| |
Collapse
|
12
|
Baró J, Martín-Olalla JM, Romero FJ, Gallardo MC, Salje EKH, Vives E, Planes A. Avalanche correlations in the martensitic transition of a Cu-Zn-Al shape memory alloy: analysis of acoustic emission and calorimetry. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2014; 26:125401. [PMID: 24599153 DOI: 10.1088/0953-8984/26/12/125401] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The existence of temporal correlations during the intermittent dynamics of a thermally driven structural phase transition is studied in a Cu-Zn-Al alloy. The sequence of avalanches is observed by means of two techniques: acoustic emission and high sensitivity calorimetry. Both methods reveal the existence of event clustering in a way that is equivalent to the Omori correlations between aftershocks in earthquakes as are commonly used in seismology.
Collapse
Affiliation(s)
- Jordi Baró
- Departament d'Estructura i Constituents de la Matèria, Facultat de Física, Universitat de Barcelona, Diagonal, 647, E-08028 Barcelona, Catalonia, Spain
| | | | | | | | | | | | | |
Collapse
|
13
|
Baró J, Vives E. Analysis of power-law exponents by maximum-likelihood maps. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 85:066121. [PMID: 23005176 DOI: 10.1103/physreve.85.066121] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Indexed: 06/01/2023]
Abstract
Maximum-likelihood exponent maps have been studied as a technique to increase the understanding and improve the fit of power-law exponents to experimental and numerical simulation data, especially when they exhibit both upper and lower cutoffs. The use of the technique is tested by analyzing seismological data, acoustic emission data, and avalanches in numerical simulations of the three-dimensional random field Ising model. In the different examples we discuss the nature of the deviations observed in the exponent maps and some relevant conclusions are drawn for the physics behind each phenomenon.
Collapse
Affiliation(s)
- Jordi Baró
- Departament d'Estructura i Constituents de la Matèria, Facultat de Física, Universitat de Barcelona, Diagonal 647, E-08028 Barcelona, Catalonia, Spain.
| | | |
Collapse
|
14
|
Brinkman BAW, Dahmen KA. Tuning coupling: discrete changes in runaway avalanche sizes in disordered media. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2011; 84:041129. [PMID: 22181109 DOI: 10.1103/physreve.84.041129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2010] [Indexed: 05/31/2023]
Abstract
Hysteretic systems may exhibit a runaway avalanche in which a large fraction of the constituents of the system collectively change state. It would be very valuable to understand the role that interaction strength between constituents plays in the size of such catastrophic runaway avalanches. We use a simple model, the random field Ising model, to study how the size of the runaway avalanche changes as the coupling between spins, J, is tuned. In particular, we calculate P(S), the distribution of size changes S in the runaway avalanche size as J comes close to a critical value J(c), and find that the distribution scales as P(S)∼S(-τ)D(S(σ)(J/J(c)-1)), with τ and σ critical exponents and D(x) a universal scaling function. In mean field theory we find τ=3/2, σ=1/2, and D(x)=exp[-(3x)(1/σ)/2]. On the basis of these results and previous studies, we also predict that for three dimensions τ=1.6 and σ=0.24.
Collapse
Affiliation(s)
- Braden A W Brinkman
- Department of Physics, University of Illinois at Urbana-Champaign, 1110 West Green Street Urbana, Illinois 61801-3080, USA
| | | |
Collapse
|
15
|
Salvat-Pujol F, Vives E, Rosinberg ML. Hysteresis in the T=0 random-field Ising model: beyond metastable dynamics. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2009; 79:061116. [PMID: 19658482 DOI: 10.1103/physreve.79.061116] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/04/2009] [Indexed: 05/28/2023]
Abstract
We present a numerical study of the zero-temperature response of the Gaussian random-field Ising model to a slowly varying external field, allowing the system to be trapped in microscopic configurations that are not fully metastable. This modification of the standard single-spin-flip dynamics results in an increase in dissipation (hysteresis) somewhat similar to that observed with a finite driving rate. We then study the distribution of avalanches along the hysteresis loop and perform a finite-size scaling analysis that shows good evidence that the critical exponents associated to the disorder-induced phase transition are not modified.
Collapse
Affiliation(s)
- Francesc Salvat-Pujol
- Departament d'Estructura i Constituents de la Matèria, Facultat de Física, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Catalonia, Spain
| | | | | |
Collapse
|
16
|
White RA, Dahmen KA. Driving rate effects on crackling noise. PHYSICAL REVIEW LETTERS 2003; 91:085702. [PMID: 14525257 DOI: 10.1103/physrevlett.91.085702] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2002] [Indexed: 05/24/2023]
Abstract
Many systems respond to slowly changing external conditions with crackling noise, created by avalanches or pulses with a broad range of sizes. Examples range from Barkhausen noise (BN) in magnets to earthquakes. In this Letter, we discuss the effects of increasing driving rate Omega on the scaling behavior of the avalanche size and duration distributions as well as qualitative effects of Omega on the power spectra. We derive an exponent inequality as a criteria for the relevance of Omega. To illustrate these general results, we use recent experiments on BN as a successful example.
Collapse
Affiliation(s)
- Robert A White
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | | |
Collapse
|
17
|
Mehta AP, Mills AC, Dahmen KA, Sethna JP. Universal pulse shape scaling function and exponents: critical test for avalanche models applied to Barkhausen noise. PHYSICAL REVIEW E 2002; 65:046139. [PMID: 12005958 DOI: 10.1103/physreve.65.046139] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2001] [Indexed: 11/07/2022]
Abstract
In order to test if the universal aspects of Barkhausen noise in magnetic materials can be predicted from recent variants of the nonequilibrium zero-temperature Random Field Ising Model, we perform a quantitative study of the universal scaling function derived from the Barkhausen pulse shape in simulations and experiment. Through data collapses and scaling relations we determine the critical exponents tau and 1/sigma nu z in both simulation and experiment. Although we find agreement in the critical exponents, we find differences between theoretical and experimental pulse shape scaling functions as well as between different experiments.
Collapse
Affiliation(s)
- Amit P Mehta
- Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA
| | | | | | | |
Collapse
|
18
|
Abstract
Crackling noise arises when a system responds to changing external conditions through discrete, impulsive events spanning a broad range of sizes. A wide variety of physical systems exhibiting crackling noise have been studied, from earthquakes on faults to paper crumpling. Because these systems exhibit regular behaviour over a huge range of sizes, their behaviour is likely to be independent of microscopic and macroscopic details, and progress can be made by the use of simple models. The fact that these models and real systems can share the same behaviour on many scales is called universality. We illustrate these ideas by using results for our model of crackling noise in magnets, explaining the use of the renormalization group and scaling collapses, and we highlight some continuing challenges in this still-evolving field.
Collapse
Affiliation(s)
- J P Sethna
- Laboratory of Atomic and Solid State Physics, Cornell University, Ithaca, New York 14853-2501, USA
| | | | | |
Collapse
|