Origin of the spin Seebeck effect in compensated ferrimagnets

Magnons are the elementary excitations of a magnetically ordered system. In ferromagnets, only a single band of low-energy magnons needs to be considered, but in ferrimagnets the situation is more complex owing to different magnetic sublattices involved. In this case, low lying optical modes exist that can affect the dynamical response. Here we...

Coherent elastic excitation of spin waves

We model the injection of elastic waves into a ferromagnetic film (F) by a nonmagnetic transducer (N). We compare the configurations in which the magnetization is normal and parallel to the wave propagation. The lack of axial symmetry in the former results in the emergence of evanescent interface states. We compute the energy-flux transmission...

Spin Hall noise

We measure the low-frequency thermal fluctuations of pure spin current in a platinum film deposited on yttrium iron garnet via the inverse spin Hall effect (ISHE)-mediated voltage noise as a function of the angle ? between the magnetization and the transport direction. The results are consistent with the fluctuation-dissipation theorem in terms...

Theoretical model for torque differential magnetometry of single-domain magnets

We present a generic theoretical model for torque differential magnetometry (TDM)—an experimental method for determining the magnetic properties of a magnetic specimen by recording the resonance frequency of a mechanical oscillator, on which the magnetic specimen has been mounted, as a function of the applied magnetic field. The effective...

Angular and linear momentum of excited ferromagnets

The angular momentum vector of a Heisenberg ferromagnet with isotropic exchange interaction is conserved, while under uniaxial crystalline anisotropy the projection of the total spin along the easy axis is a constant of motion. Using Noether's theorem, we prove that these conservation laws persist in the presence of dipole-dipole interactions....

Magnon, phonon, and electron temperature profiles and the spin Seebeck effect in magnetic insulator/normal metal hybrid structures

We calculate the phonon, electron, and magnon temperature profiles in yttrium iron garnet/platinum bilayers by diffusive theory with appropriate boundary conditions, in particular taking into account interfacial thermal resistances. Our calculations show that in thin film hybrids, the interface magnetic heat conductance qualitatively affects the...