Nonlocal feedback in ferromagnetic resonance

Nonlocal magnetization dynamics in ferromagnetic heterostructures

Yaroslav Tserkovnyak, Arne Brataas, Gerrit E. W. Bauer, and Bertrand I. Halperin Lyman Laboratory of Physics, Harvard University, Cambridge, Massachusetts 02138, USA Department of Physics, Norwegian University of Science and Technology, N-7491 Trondheim, Norway Kavli Institute of NanoScience, Delft University of Technology, 2628 CJ Delft, The Netherlands Lyman Laboratory of Physics, Harvard Uni...

Nonlocal magnetization dynamics in ferromagnetic hybrid nanostructures

Two complementary effects modify the GHz magnetization dynamics of nanoscale hybrid structures of ferromagnetic and normal materials from those of the isolated magnetic constituents: On the one hand, a time-dependent ferromagnetic magnetization pumps a spin angular-momentum flow into adjacent materials and, on the other hand, spin angular momentum is transferred between ferromagnets by an appli...

Ferromagnetic resonance

Ferromagnetic Resonance

Ferromagnetism is used to characterize magnetic behavior of a material, such as the strong attraction to a permanent magnet. The origin of this strong magnetism is the presence of a spontaneous magnetization which is produced by a parallel alignment of spins. Instead of a parallel alignment of all the spins, there can be an anti-parallel alignment of unequal spins. This results in a spontaneous...

Nonlocal feedback in nonlinear systems

A shifted or misaligned feedback loop gives rise to a two-point nonlocality that is the spatial analog of a temporal delay. Important consequences of this nonlocal coupling have been found both in diffusive and in diffractive systems, and include convective instabilities, independent tuning of phase and group velocities, as well as amplification, chirping and even splitting of localized perturb...