https://doi.org/10.1140/epjb/e2005-00371-4
Magnetotransport properties of nano-constriction array in La0.67Sr0.33MnO3 film
1
Centre for Superconducting and Magnetic Materials,
Department of Physics, National University of Singapore, 2 Science
Drive 3, Singapore 117542, Singapore
2
Data Storage Institute,
5 Engineering Drive 1, DSI Building, Singapore 117608, Singapore
Corresponding author: a g0306128@nus.edu.sg
Received:
14
May
2005
Published online:
9
December
2005
Nano-constriction array in La0.67Sr0.33MnO3 film was fabricated by using ion beam etching masked by a monolayer of packed and ordered array of SiO2 microspheres. Nano-constrictions of around 50 nm in width were fabricated. The low field magnetoresistance (LFMR) exhibited in the samples were observed to be current dependent and the I-V characteristics of the film were found to be nonlinear. These observations were attributed to the co-existence of the ferromagnetic regions and the nano-constricted region of weakened ferromagnetic coupling where Mn3+-O-Mn4+ bond were distorted due to the ion beam bombardment. The spin polarized bias current would strengthen local ferromagnetic coupling when passing through this nano-constricted regions. This current effect is relatively large comparing to the external magnetic field to the drop of resistance.
PACS: 75.47.Lx – Manganites / 73.63.Rt – Nanoscale contacts
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2005