Related papers: Nonlinear relaxation between magnons and phonons i…
The discrete rotational symmetry of crystals leads to the conservation of quantized angular momentum in solids. While the exchange of energy and linear momentum between lattice vibrations (phonons) via anharmonic coupling is a cornerstone…
A magnon and a phonon are the quanta of spin wave and lattice wave, respectively, and they can hybridize into a magnon polaron when their frequencies and wavenumbers match close enough the values at the exceptional point. Guided by an…
We study the electron-phonon relaxation in the model of a granular metal film, where the grains are formed by regularly arranged potential barriers of arbitrary transparency. The relaxation rate of Debye acoustic phonons is calculated,…
We theoretically explore the generation of spin current driven by a temperature gradient in a junction between a chiral insulator and a normal metal. Based on the gyromagnetic response induced by microscopic acoustic-phonon-mediated lattice…
We present the detailed inelastic neutron scattering measurements of the noncollinear antiferromagnet Mn$_3$Ge. Time-of-flight and triple-axis spectroscopy experiments were conducted at the temperature of 6~K, well below the high magnetic…
While the vibrational thermodynamics of materials with small anharmonicity at low temperatures has been understood well based on the harmonic phonons approximation; at high temperatures, this understanding must accommodate how phonons…
We study the electron spin resonance in a dilute magnon gas that is realized in a ferromagnetic spin system at low temperature. A quantum cluster expansion is developed to show that the frequency shift of the single-magnon peak changes its…
Within the Dyson-Maleev boson formalism, we study the zero-temperature magnon dispersions in a family of one-dimensional quantum Heisenberg ferrimagnets composed of two different spins $(S_1,S_2)$ in the elementary cell. It is shown that…
The linear and nonlinear processes in ferromagnetic films at low temperatures T<< Tc are studied in a microscopic theory. Both the long-range magnetic dipole-dipole and the Heisenberg exchange interactions to nearest and next-nearest…
We have carried out an extensive phonon study on multiferroic GaFeO3 to elucidate its dynamical behavior. Inelastic neutron scattering measurements are performed over a wide temperature range, 150 to 1198 K. First principles lattice…
A model calculation is given for the energy relaxation of a non-equilibrium distribution of hot electrons prepared in a metallic sample that has been subjected to homogeneous photo-excitation by a femtosecond laser pulse. The model assumes…
We make a modified spin-wave description of the nuclear spin relaxation in Heisenberg alternating-spin chains with antiferromagnetic exchange coupling. In contrast with the conventional one-dimensional antiferromagnetic spin-wave theory,…
A previously proposed variational approach for momentum-conserving systems [J. Liu et.al., Phys. Rev. E 91, 042910 (2015)] is extended to systematically investigate general momentum-nonconserving nonlinear lattices. Two intrinsic identities…
We have formulated a relaxation mechanism for ferrites and ferromagnetic metals whereby the coupling between the magnetic motion and lattice is based purely on continuum arguments concerning magnetostriction. This theoretical approach…
The electron-phonon coupling and the corresponding energy exchange was investigated experimentally and by ab initio theory in non-equilibrium states of the free-electron metal aluminium. The temporal evolution of the atomic mean squared…
Spin-lattice relaxation is a key open problem to understand the spin dynamics of single-molecule magnets and molecular spin qubits. While modelling the coupling between spin states and local vibrations allows to determine the more relevant…
The magnetic excitations in ferromagnetic SrRuO$_3$ were studied by inelastic neutron scattering combining experiments on triple-axis and time-of-flight spectrometers with and without polarization analysis. A quadratic spin-wave dispersion…
We investigated the magnetic and magnetoelastic properties of MnSc$_2$Se$_4$ single crystals at low temperature under a magnetic field directed along the crystallographic [111] axis. The magnetization data at low temperature show a linear…
The description of nonequilibrium states of solids in a simplified manner is a challenge in the field of ultrafast dynamics. Here, the phonon thermalization in solids through the three-phonon scatterings is investigated by solving the…
We report predominantly zero field muon spin relaxation measurements in a series of Ca-doped LaMnO_3 compounds which includes the colossal magnetoresistive manganites. Our principal result is a systematic study of the spin-lattice…