What is the Physical Explanation for the Very Large Ballistic Magnetoresitance Observed in Electrodeposited Nanocontacts?

N. Garcia

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What is the Physical Explanation for the Very Large Ballistic Magnetoresitance Observed in Electrodeposited Nanocontacts?

N. Garcia

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Abstract

Recent experiments in approximately 10nm size electrodeposited Ni-Ni nanocontacts have shown ballistic magnetoresitance values of 700% stable during a week (Garcia et al Appl. Phys. Lett. 79, 4550(2001) and very recently up to 3000% (Chopra and Hua, Phys. Rev. B 66,020403-1 (2002)). These values can provide very interesting magnetoelectronic devices integrated in the terabyte/square inch. Scattering in thin domain wall of the Ni-Ni nanocontacts, or quantized effects phenomena do not explain these values. An explanation is presented that requires the existence of a very thin, less than 1nm, dead magnetic layer grown during the electrodeposition process that is transparent to the electrons and has two roles: one, is to conserve spin in the electron conduction and the other, is to change and increase the polarization at Fermi level in the Ni.

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N. Garcia. 2002-07-12. What is the Physical Explanation for the Very Large Ballistic Magnetoresitance Observed in Electrodeposited Nanocontacts?. https://arxiv.org/abs/cond-mat/0207323

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