Galvanomagnetic Effect of a Cross-Shaped Magnetic Wire on a Mesoscopic Scale.

A cross-shaped Co wire on a mesoscopic scale was fabricated by using electron-beam lithography, and the galvanomagnetic effect was measured at room temperature. Many jumps in the Hall resistance were observed. In order to explain these jumps, exchange interactions with the current and voltage probes were considered, and the Hall resistance was calculated. The calculated result reproduced three jumps in the observed Hall resistance. It was found that the Hall resistance curve of a cross-shaped wire can be controlled by the ratio of the coercive forces of the magnetizations of the probes. The magnetoresistance of a narrow wire with two crossing points was understood by using the present model to calculate the magnetization process.