Abstract
C. E. Zaspel
Soliton Velocities in Magnetic Thin Films
Department of Environmental Sciences
University of Montana/Western
Dillon, MT 59725
Department of Physics
Montana State University
Bozeman, Mt 59717
Soliton formation from an initial rectangular pulse and soliton propagation
in magnetic thin films such as yttrium iron garnet have been successfully
modeled by the nonlinear Schroedinger (NLS) equation containing second
order linear dispersion and cubic nonlinear self-frequency shift. There
are, however, some experimental effects that are not obvious consequences
of the NLS model. One example is the observed [1] dependence of the soliton
velocity on both the initial pulse amplitude and pulse duration, but in the
single soliton solution of the NLS equation the soliton velocity is an
arbitrary parameter with no clear relation to the initial pulse parameters.
It is shown here that the NLS solution does indeed establish a relation
between the soliton velocity and the initial pulse amplitude and duration.
This is done using the assumption that the nonlinear self-frequency shift
balances the linear dispersive effects resulting in stable soliton
propagation. Finally, the NLS conservation laws are used to show that the
soliton velocity is not an arbitrary pararmeter, but it is proportional to
the initial pulse power and duration.
[1] H. Xia, P. Kabos, R A. Staudinger, C. E. Patton, and A. N. Slavin,
Phys. Rev. B, 58, 2708 (1998).
Return to
Return to conference page