First-principles calculations for Gilbert damping constant at finite temperature

Applied Physics Express ◽

10.35848/1882-0786/ac4205 ◽

2021 ◽

Author(s):

Ryoya Hiramatsu ◽

Daisuke Miura ◽

Akimasa SAKUMA

Keyword(s):

First Principles ◽

Finite Temperature ◽

Spin Fluctuation ◽

Tight Binding ◽

First Principles Calculation ◽

Transverse Spin ◽

Orbital Method ◽

Correlation Model ◽

Gilbert Damping ◽

Experimental Values

Abstract We propose a first-principles calculation method for the Gilbert damping constants α at finite temperatures. α is described by the torque correlation model in which the electronic structure is computed by the tight-binding linear muffin-tin orbital method. We include the finite-temperature effect as the transverse spin fluctuation in the disordered local moment picture within the coherent potential approximation. Applying the present method to bcc-Fe and L10-FePt, we demonstrate these temperature-dependent α. By comparing our calculated results with experimental results, we find the calculated values are less than half of the experimental values, reflecting the characteristics of the torque correlation model.

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First-principles calculation of the effects of tetragonal distortions on the Gilbert damping parameter of Co2MnSi

AIP Advances ◽

10.1063/1.4974525 ◽

2017 ◽

Vol 7 (5) ◽

pp. 056009

Author(s):

B. Pradines ◽

R. Arras ◽

L. Calmels

Keyword(s):

First Principles ◽

First Principles Calculation ◽

Gilbert Damping ◽

Damping Parameter

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First-principles study of the Gilbert damping constants of Heusler alloys based on the torque correlation model

Journal of Physics D Applied Physics ◽

10.1088/0022-3727/48/16/164011 ◽

2015 ◽

Vol 48 (16) ◽

pp. 164011 ◽

Cited By ~ 21

Author(s):

Akimasa Sakuma

Keyword(s):

First Principles ◽

Heusler Alloys ◽

Correlation Model ◽

Gilbert Damping ◽

First Principles Study

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First principles calculation for hydrogen/positronium adsorption on an Si(111) surface using the dynamical extended molecular orbital method

Surface Science ◽

10.1016/s0039-6028(99)00551-8 ◽

1999 ◽

Vol 438 (1-3) ◽

pp. 47-57 ◽

Cited By ~ 10

Author(s):

Mayumi Ishida ◽

Masanori Tachikawa ◽

Hiroaki Tokiwa ◽

Kazuhide Mori ◽

Akira Ishii

Keyword(s):

Molecular Orbital ◽

First Principles ◽

First Principles Calculation ◽

Orbital Method ◽

Molecular Orbital Method

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First-Principles Calculation on the Emission Energy Level of Ruby Based on DV-Xα Molecular Orbital Method and Ligand Field Theory

ECS Meeting Abstracts ◽

10.1149/ma2016-02/42/3176 ◽

2016 ◽

Keyword(s):

Field Theory ◽

Energy Level ◽

Molecular Orbital ◽

First Principles ◽

First Principles Calculation ◽

Orbital Method ◽

Ligand Field ◽

Molecular Orbital Method ◽

Ligand Field Theory ◽

Emission Energy

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Ab Initio Study of Pressure-Induced Structural Properties of Uranium Chalcogenides

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1047.155 ◽

2014 ◽

Vol 1047 ◽

pp. 155-161

Author(s):

Archana Singh ◽

Mahendra Aynyas ◽

S.P. Sanyal

Keyword(s):

Phase Transition ◽

Structural Phase Transition ◽

Phase Structure ◽

Structural Phase ◽

Tight Binding ◽

First Principles Calculation ◽

Orbital Method ◽

Cscl Type ◽

Spin Polarized ◽

Total Energies

We report a first principles calculation of pressure-induced structural phase transition properties of uranium chalcogenides (UX; X=S, Se and Te). The total energies as a function of volume are obtained by means of self-consistent tight binding linear muffin orbital method (TB-LMTO) by performing spin and non-spin polarized calculations to determine the magnetic and structural stabilities. From the present study, we predict a magnetic phase transition from ferromagnetic (FM) to non-magnetic (NM) state around 67.7 and 10.2 GPa for US and USe, respectively. The pressure-induced magnetic transitions are found second-order in nature. We have also predicted structural phase transition from FM-NaCl-type (B1phase) structure to NM-CsCl-type (B2phase) structure at around 77.5, 23.5 for US and USe, respectively, while UTe undergoes from FM-B1to FM-B2phase around 12.0 GPa.

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First Principles Calculations of Thermodynamic Quantities and Phase Diagrams of High Temperature BCC Ta-W and Mo-Ta Alloys

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.26-28.205 ◽

2007 ◽

Vol 26-28 ◽

pp. 205-208

Author(s):

Kinichi Masuda-Jindo ◽

Vu Van Hung ◽

P.E.A. Turchi

Keyword(s):

High Temperature ◽

Phase Diagrams ◽

First Principles ◽

Equilibrium Phase ◽

Tight Binding ◽

Configurational Entropy ◽

Variation Method ◽

Orbital Method ◽

Thermodynamic Quantities ◽

Cluster Approximation

The thermodynamic properties of high temperature metals and alloys are studied using the statistical moment method, going beyond the quasi-harmonic approximations. Including the power moments of the atomic displacements up to the fourth order, the Helmholtz free energies and the related thermodynamic quantities are derived explicitly in closed analytic forms. The configurational entropy term is taken into account by using the tetrahedron cluster approximation of the cluster variation method (CVM). The energetics of the binary (Ta-W and Mo-Ta) alloys are treated within the framework of the first-principles TB-LMTO (tight-binding linear muffin tin orbital) method coupled to CPA (coherent potential approximation) and GPM (generalized perturbation method). The equilibrium phase diagrams are calculated for the refractory Ta-W and Mo-Ta bcc alloys.

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First-principles calculation of the Gilbert damping parameter via the linear response formalism with application to magnetic transition metals and alloys

Physical Review B ◽

10.1103/physrevb.87.014430 ◽

2013 ◽

Vol 87 (1) ◽

Cited By ~ 74

Author(s):

S. Mankovsky ◽

D. Ködderitzsch ◽

G. Woltersdorf ◽

H. Ebert

Keyword(s):

Transition Metals ◽

First Principles ◽

Linear Response ◽

Magnetic Transition ◽

Metals And Alloys ◽

First Principles Calculation ◽

Gilbert Damping ◽

Damping Parameter

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Insight into Physical and Thermodynamic Properties of X3Ir (X = Ti, V, Cr, Nb and Mo) Compounds Influenced by Refractory Elements: A First-Principles Calculation

Crystals ◽

10.3390/cryst9020104 ◽

2019 ◽

Vol 9 (2) ◽

pp. 104 ◽

Cited By ~ 2

Author(s):

Dong Chen ◽

Jiwei Geng ◽

Yi Wu ◽

Mingliang Wang ◽

Cunjuan Xia

Keyword(s):

Thermodynamic Properties ◽

First Principles ◽

Density Functional ◽

Local Density ◽

First Principles Calculation ◽

Generalized Gradient ◽

Functional Theory ◽

Debye Temperatures ◽

Experimental Parameters ◽

Experimental Values

The effects of refractory metals on physical and thermodynamic properties of X3Ir (X = Ti, V, Cr, Nb and Mo) compounds were investigated using local density approximation (LDA) and generalized gradient approximation (GGA) methods within the first-principles calculations based on density functional theory. The optimized lattice parameters were both in good compliance with the experimental parameters. The GGA method could achieve an improved structural optimization compared to the LDA method, and thus was utilized to predict the elastic, thermodynamic and electronic properties of X3Ir (X = Ti, V, Cr, Nb and Mo) compounds. The calculated mechanical properties (i.e., elastic constants, elastic moduli and elastic anisotropic behaviors) were rationalized and discussed in these intermetallics. For instance, the derived bulk moduli exhibited the sequence of Ti3Ir < Nb3Ir < V3Ir < Cr3Ir < Mo3Ir. This behavior was discussed in terms of the volume of unit cell and electron density. Furthermore, Debye temperatures were derived and were found to show good consistency with the experimental values, indicating the precision of our calculations. Finally, the electronic structures were analyzed to explain the ductile essences in the iridium compounds.

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