Microscopic spin-wave theory for yttrium-iron garnet films

Microscopic spin-wave theory for yttrium-iron garnet films

Motivated by recent experiments on thin films of the ferromagnetic insulator yttrium-iron garnet (YIG), we have developed an efficient microscopic approach to calculate the spin-wave spectra of these systems. We model the experimentally relevant magnon band of YIG using an effective quantum Heisenberg model on a cubic lattice with ferromagnetic nearest neighbour exchange and long-range dipole-d...

Spin-Wave Spectra of Yttrium and Gadolinium Iron Garnet

The problem of deducing the values of the exchange integrals in yttrium and gadolinium iron garnet from measurements of the magnetization and the magnetic contribution to the specific heat at low temperatures is considered. For these garnets the spin-wave normal modes can be found by solving the semiclassical equations of motion which give rise to a set of n simultaneous linear equations, where...

Generation of coherent spin-wave modes in yttrium iron garnet microdiscs by spin–orbit torque

In recent years, spin-orbit effects have been widely used to produce and detect spin currents in spintronic devices. The peculiar symmetry of the spin Hall effect allows creation of a spin accumulation at the interface between a metal with strong spin-orbit interaction and a magnetic insulator, which can lead to a net pure spin current flowing from the metal into the insulator. This spin curren...

Role of damping in spin Seebeck effect in yttrium iron garnet thin films

The role of damping in the spin Seebeck effect (SSE) was studied experimentally for the first time. The experiments used Y3Fe5O12 (YIG)/Pt bilayered structures where the YIG films exhibit very similar structural and static magnetic properties but very different damping. The data show that a decrease in the damping gives rise to an increase in the SSE coefficient, which is qualitatively consiste...

HighQ magnetostatic surface wave planar yttrium iron garnet resonator