1202.1920 (Yutaka Sakai et al.)

Observation of Huge Magnetoresistance and Multiferroic-like Behavior of
Co Nanoparticles in a C60 matrix    [PDF]

Yutaka Sakai, Eiiti Tamura, Shuhei Toyokawa, Eiji Shikoh, Vlado K. Lazarov, Atsufumi Hirohata, Teruya Shinjo, Yoshishige Suzuki, Masashi Shiraishi

Tunneling magnetoresistance (TMR) via oxides or molecules includes fruitful
physics, such as spin filtering and hybridized interface states, in addition to
various practical applications using large TMR ratio at room temperature. Then,
a larger TMR effect with a new fundamental physics is awaited because further
progress on spintronics can be realized. Here we report a discovery of a
gigantic TMR ratio of 1,400,000% in a C60-Co nanocomposite spin device. The
observed effect is induced by a combination of a Coulomb blockade effect and a
novel magnetic switching effect. Theoretical investigation reveals that an
electric field and a magnetic field control the magnetization and the
electronic charging state, respectively, of the Co nanoparticles as in physics
of multiferroicity.

View original: http://arxiv.org/abs/1202.1920