Atomistic Simulation of Phonon and Magnon Thermal Transport across the Ferro-Paramagnetic Transition

Abstract

A temperature-dependent approach involving Green-Kubo equilibrium atomic and spin dynamics (GKEASD) is reported to assess phonon and magnon thermal transport processes accounting for phonon-magnon interactions. Using body-center cubic (BCC) iron as a case study, GKEASD successfully reproduces its characteristic temperature-dependent spiral and lattice thermal conductivities. The non-electronic thermal conductivity, i.e., the sum of phonon and magnon thermal conductivities, calculated using GKEASD for BCC Fe agrees well with experimental measurements. Spectral energy analysis reveals that high-frequency phonon-magnon scattering rates are one order of magnitude larger than those at low frequencies due to energy scattering conservation rules and high densities of states. Higher temperatures further accentuate this phenomenon. This new framework fills existing gaps in simulating thermal transport across the ferro- to para-magnetic transition. Future application of this methodology to phonon- and magnon-dominant insulators and semiconductors will enhance understanding of emerging thermoelectric, spin caloritronic and superconducting materials.

References in corpus (15)

• Spin Caloritronics
• Ab-initio calculations of exchange interactions, spin-wave stiffness constants, and Curie temperatures of Fe, Co, and Ni
• Acoustic spin pumping as the origin of the long-range spin Seebeck effect
• Cooling and heating with electron spins: Observation of the spin Peltier effect
• Massively parallel symplectic algorithm for coupled magnetic spin dynamics and molecular dynamics
• Quantitatively Analyzing Phonon Spectral Contribution of Thermal Conductivity Based on Non-Equilibrium Molecular Dynamics Simulation I: From Space Fourier Transform
• Anomalous phonon lifetime shortening in paramagnetic CrN caused by magneto-lattice coupling: A combined spin and ab initio molecular dynamics study
• Magnon and Phonon Dispersion, Lifetime and Thermal Conductivity of Iron from Spin-Lattice Dynamics Simulations
• Atomic configuration and properties of austenitic steels at finite temperature: The effect of longitudinal spin fluctuations
• Realistic finite temperature simulations of magnetic systems using quantum statistics
• Generalized two-temperature model for coupled phonon-magnon diffusion
• Nonharmonic Phonons in $\alpha$-Iron at High Temperatures
• Magnon-phonon relaxation in yttrium iron garnet from first principles
• Thermal conductivity in large-$J$ two-dimensional antiferromagnets: Role of phonon scattering
• Thermal conductivity of local moment models with strong spin-orbit coupling

Cited by in corpus (5)

• Quantum-accurate magneto-elastic predictions with classical spin-lattice dynamics
• Spin-lattice model for cubic crystals
• Size and temperature dependent magnetization of iron nanoclusters
• Roadmap on Quantum Magnetic Materials
• Spin-lattice couplings in $3d$ ferromagnets: analysis from first-principles