Transport properties of during the to structural phase transition

Abstract

The variation of transport behavior in a mesoscopic $\mathrm{Fe}_{60}\mathrm{Al}_{40}$ wire, initially possessing the ordered $B2$ -phase structure, has been observed while inducing a phase transition to the disordered $A2$ phase. Gradual disordering was achieved using a highly focused beam of $\mathrm{Ne}^+$ -ions. Both electrical resistance and anomalous Hall effect were measured simultaneously and in situ during the local ion irradiation. The normal as well as the Hall resistivity show a peak as a function of disorder. The relationship between Hall resistivity and normal resistivity shows the presence of two distinct transport regimes during the phase transition. Ex situ field- and temperature-dependence measurements show that it is necessary to consider the effect of scattering from magnetic clusters to understand these different regimes in transport properties.

Keywords

• magnetism
• ion beams
• phase transitions
• transport
• magnetic clusters
• disorder