Damping of confined modes in a ferromagnetic thin insulating film: angular momentum transfer across a nanoscale field-defined interface.
We observe a dependence of the damping of a confined mode of precessing ferromagnetic magnetization on the size of the mode. The micron-scale mode is created within an extended, unpatterned yttrium iron garnet film by means of the intense local dipolar field of a micromagnetic tip. We find that the damping of the confined mode scales like the surface-to-volume ratio of the mode, indicating an interfacial damping effect (similar to spin pumping) due to the transfer of angular momentum from the confined mode to the spin sink of ferromagnetic material in the surrounding film. Though unexpected for insulating systems, the measured intralayer spin-mixing conductance g_↑↓=5.3×10(19)  m(-2) demonstrates efficient intralayer angular momentum transfer.
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Rohan
R
Adur
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Chunhui
C
Du
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Hailong
H
Wang
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Sergei A
SA
Manuilov
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Vidya P
VP
Bhallamudi
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Chi
C
Zhang
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Denis V
DV
Pelekhov
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
Fengyuan
F
Yang
Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA.
P Chris
PC
Hammel