474 research outputs found
Intrinsic Spin Hall Effect
A brief review is given on the spin Hall effect, where an external electric
field induces a transverse spin current. It has been recognized over 30 years
that such effect occurs due to impurities in the presence of spin-orbit
coupling. Meanwhile, it was proposed recently that there is also an intrinsic
contribution for this effect. We explain the mechanism for this intrinsic spin
Hall effect. We also discuss recent experimental observations of the spin Hall
effect.Comment: 13 pages, 3 figures, to appear in Advances in Solid State Physics,
Vol 45(2005), edited by B. Kramer, changes in Sections 3 and 4.
Spin Hall Effect in p-type Semiconductors
The spin Hall effect is a phenomenon of inducing spin current by an external
electric field. We recently proposed that this effect can occur in p-type
semiconductors without relying upon any disorder scattering [S. Murakami et
al., Science 301, 1348 (2003)]. This intrinsic effect is due to the ``Berry
phase in momentum space'', representing topological structure of the Bloch band
structure. We explain how the Berry phase brings about the spin Hall effect,
and review several interesting aspects of this effectComment: 6 pages, 1 figure, prepared for Proceedings of International
Symposium on Mesoscopic Superconductivity and Spintronics 2004 (Atsugi,
Japan, March 1-4, 2004
Theoretical prediction of rotating magnon wavepacket in ferromagnets
We theoretically show that the magnon wavepacket has a rotational motion in
two ways; a self-rotation and a motion along the boundary of the sample (edge
current). They are similar to cyclotron motion of electrons, but unlike
electrons the magnons have no charge and the rotation is not due to Lorenz
force. These rotational motions are caused by the Berry phase in momentum space
from magnon band structure. Furthermore, these rotational motions of the magnon
give an additional correction term to the magnon Hall effect. We also discuss
the Berry curvature effect in the classical limit of long-wavelength
magnetostatic spin waves having macroscopic coherence length.Comment: 4pages, 2figures, accepted for publication in Phys. Rev. Let
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