Magnetoresistance of magnetite point contacts and nanoconstrictions
Citation:
O. Cespedes, E. Clifford and J.M.D. Coey, 'Magnetoresistance of magnetite point contacts and nanoconstrictions' in Journal of Applied Physics, 97, (6), 2005, 064305Download Item:
Abstract:
Point contacts of magnetite exhibit large, reversible increases of conductance by a factor of up to 5 in the presence of a small magnetic field (<10?mT), provided the conductance is less than the quantum of conductance G0 (12?900??)?1. Smaller effects are found in (La0.7Sr0.3)MnO3 and Co2Cr0.6Fe0.4Al. Comparable effects observed in magnetite nanoconstrictions milled using a focused-ion beam in thin films deposited on oxide substrates are only reversible on a time scale of hours. High-resistance nanogaps show evidence of field emission beyond a voltage threshold, which is itself field dependent. The results are discussed in terms of spin-polarized transport, magnetostriction, magnetic dipole strain, and Fowler?Nordheim tunneling.
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Enterprise Ireland
Science Foundation Ireland
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http://people.tcd.ie/jcoeyDescription:
PUBLISHED
Author: COEY, JOHN MICHAEL DAVID
Sponsor:
Enterprise IrelandScience Foundation Ireland
Publisher:
American Institute of PhysicsCollections
Series/Report no:
Journal of Applied Physics97
6
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