Tunneling and anisotropic-tunneling magnetoresistance in iron nanoconstrictions fabricated by focused-ion-beam

Fernandez-Pacheco, A. , De Teresa, J. M., Cordoba, R. and Ibarra, R. (2011) Tunneling and anisotropic-tunneling magnetoresistance in iron nanoconstrictions fabricated by focused-ion-beam. MRS Online Proceedings Library, 1181, DD02-03. (doi: 10.1557/proc-1181-dd02-03)

Abstract

We report the magnetoresistance (MR) measurements in a nanoconstriction fabricated by focused-ion-beam (FIB) in the tunneling regime of conductance. The resistance of the contact was controlled during the fabrication process, being stable in the metallic regime, near the conductance quantum, and under high vacuum conditions. The metallic contact was deteriorated when exposed to atmosphere, resulting in a conduction mechanism by tunneling. The TMR was found to be of 3% at 24 K. The anisotropic tunneling magnetoresistance (TAMR) was around 2% for low temperatures, with a field angle dependence more abrupt than in bulk Fe. This preliminary result is promising for the application of this technique to fabricate stable ferromagnetic constrictions near the atomic regime of conductance, where high MR values are expected.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fernandez-Pacheco, Dr Amalio
• Authors: Fernandez-Pacheco, A., De Teresa, J. M., Cordoba, R., and Ibarra, R.
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Journal Name: MRS Online Proceedings Library
• Publisher: Cambridge University Press
• ISSN: 1946-4274