Abstract:
Present information technology is based on electron transport and
magnetism.
Magnetism has been most successful in high-density storages such as hard
disks.
For integration of magnetic storages into electronic circuits, mechanisms
are necessary to convert electric current/voltage into magnetic
information and vice versa.
The most common and oldest electro-magnetic coupling is the one arising
from Maxwell's equations.
Ampere's law or Oersted's law, discovered in the early nineteenth century,
describes the magnetic field created by an electric current, and the
Faraday's law provides us means to convert magnetic information into
electric current or voltage.
In the talk, novel magnetoelectric effects in solids are discussed. They
arise from the quantum mechanical sd interaction, and have higher
efficiency in small systems than the Maxwell's mechanism.
The first is the current-induced magnetization switching[1], and the second
is the generation of electric
current by magnetization dynamics (the inverse spin Hall effect)[2-4].
References:
[1] G. Tatara, H. Kohno and J. Shibata, Phys. Rep. 468, 213 (2008).
[2] E. Saitoh et al., Appl. Phys. Lett. 182509 (2006).
[3] J. Ohe, A. Takeuchi and G.Tatara, Phys. Rev. Lett. 99, 266603 (2007).
[4] A. Takeuchi,G. Tatara, J. Phys. Soc. Jpn. 77, 074701 (2008).
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