Scaling exponent within the side-jump mechanism of Hall effect size-dependence in Ni nanocrystals

High- resolution Hall data in only 3.5 mu g of Ni nanocrystals, grown in a planar array on TiN, are reported. We conclude from the exponent, n similar to 1.06 +/- 0.01 in R-s similar to rho(n), where R-s is the extraordinary Hall constant and rho is the Ohmic resistivity, that the side- jump mechanism could still be operative if the nanocrystals are below a certain critical size and the mean free path of the electrons is strongly temperature dependent only in the magnetic layer. Also, the 1000 times larger value of Rs than those in bulk Ni makes it an ideal candidate for magnetic sensors. (C) 2008 American Institute of Physics.