TY - JOUR
T1 - Enhanced Magnetoresistance in Insulating Granular Systems
T2 - Evidence for Higher-Order Tunneling
AU - Mitani, S.
AU - Takahashi, S.
AU - Takanashi, K.
AU - Yakushiji, K.
AU - Maekawa, S.
AU - Fujimori, H.
PY - 1998/9/28
Y1 - 1998/9/28
N2 - We study the temperature and bias-voltage dependence of the magnetoresistance (MR) in insulating Co-Al-O granular films. The MR exhibits strong temperature dependence and is enhanced more than 20% at low temperatures, while it has no appreciable change in the bias-voltage dependence. The results provide clear evidence for the successive onset of higher-order processes of spin-dependent tunneling between large granules through intervening small ones with strong Coulomb blockade. The remarkable contrast between the temperature and bias-voltage dependence of the MR is consistently explained.
AB - We study the temperature and bias-voltage dependence of the magnetoresistance (MR) in insulating Co-Al-O granular films. The MR exhibits strong temperature dependence and is enhanced more than 20% at low temperatures, while it has no appreciable change in the bias-voltage dependence. The results provide clear evidence for the successive onset of higher-order processes of spin-dependent tunneling between large granules through intervening small ones with strong Coulomb blockade. The remarkable contrast between the temperature and bias-voltage dependence of the MR is consistently explained.
UR - http://www.scopus.com/inward/record.url?scp=0032575826&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0032575826&partnerID=8YFLogxK
U2 - 10.1103/PhysRevLett.81.2799
DO - 10.1103/PhysRevLett.81.2799
M3 - Article
AN - SCOPUS:0032575826
VL - 81
SP - 2799
EP - 2802
JO - Physical Review Letters
JF - Physical Review Letters
SN - 0031-9007
IS - 13
ER -