TY - JOUR
T1 - Tunnel magnetoresistance of C60 -Co nanocomposites and spin-dependent transport in organic semiconductors
AU - Miwa, Shinji
AU - Shiraishi, Masashi
AU - Tanabe, Shinichi
AU - Mizuguchi, Masaki
AU - Shinjo, Teruya
AU - Suzuki, Yoshishige
PY - 2007/12/19
Y1 - 2007/12/19
N2 - Magnetization, electrical conduction, and magnetoresistance (MR) of C60 -Co nanocomposites, where Co nanoparticles are dispersed in C60 molecules, have been investigated over a wide temperature range and Co volume fraction. The C60 -Co nanocomposites exhibit MR when the Co volume fraction is controlled in such a way that the conduction mechanism is dominated by tunneling of carriers between Co nanoparticles in the C60 matrix. The MR, which is attributed to spin-polarized tunneling through the C60 molecules, shows strong temperature dependence. Our results indicate that some paramagnetic components contribute to the observed MR. The material-dependent bias-voltage dependence of the MR ratio suggests that these paramagnetic components originate from the interface between organics and ferromagnets. The present study advances the fundamental understanding of spin-dependent transport in organic semiconductors.
AB - Magnetization, electrical conduction, and magnetoresistance (MR) of C60 -Co nanocomposites, where Co nanoparticles are dispersed in C60 molecules, have been investigated over a wide temperature range and Co volume fraction. The C60 -Co nanocomposites exhibit MR when the Co volume fraction is controlled in such a way that the conduction mechanism is dominated by tunneling of carriers between Co nanoparticles in the C60 matrix. The MR, which is attributed to spin-polarized tunneling through the C60 molecules, shows strong temperature dependence. Our results indicate that some paramagnetic components contribute to the observed MR. The material-dependent bias-voltage dependence of the MR ratio suggests that these paramagnetic components originate from the interface between organics and ferromagnets. The present study advances the fundamental understanding of spin-dependent transport in organic semiconductors.
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U2 - 10.1103/PhysRevB.76.214414
DO - 10.1103/PhysRevB.76.214414
M3 - Article
AN - SCOPUS:37349044295
VL - 76
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 0163-1829
IS - 21
M1 - 214414
ER -