Spin Current
Sadamichi Maekawa
Advanced Science Research Center, Japan Atomic Energy Agency,
Tokai, Japan
Spintronics is not just a new type of electronics in the 21th century [1,2] but
provides a variety of new physics [3].
The flow of electron spin, the so-called “spin current”, is a key concept in
spintronics. When the spin current interacts with the magnetic moment in a
ferromagnetic metal, the angular momentum and energy conservations give rise to the
spin transfer torque and spinmotive force. When it is injected into a non-magnetic metal
attached to a ferromagnet, the electric current is induced through the spin-charge
conversion mechanism (spin Hall effect). The generation and manipulation of the spin
current and a variety of novel phenomena given by the spin current are discussed.
Thermally driven spin current generation, i.e., the spin Seebeck effect [4], is examined
in detail.
References:
[1] Concept in Spin Electronics, ed. S. Maekawa (Oxford University Press, 2006).
[2] Spin Current, eds. S. Maekawa et al. (Oxford University Press, 2012).
[3] S. Maekawa et al., J. Phys. Soc. Jpn. 82, 102002 (1-23) (2013).
[4] K. Uchida et al., Nature 455, 778 (2008).