Correlation of magnetic property with electrical transport property for ferromagnetic (Zn1−xMnx)O thin films

Abstract

The correlation of electrical properties with magnetic properties for As+-implanted p-(Zn0.93Mn0.07)O thin films was investigated. For electrical transport measurements, it was clearly observed that the electrical mobility at the cryogenic temperature region is increased with decreasing temperatures. In Arrhenius plots of the carrier mobility, the critical point was observed at 65K. For Arrhenius plots of Mn2+-related emissions in photoluminescence measurements, the similar behavior was also observed at the same temperature region. The values of critical points are very closed to the value of the Curie temperature, thus it is expected that the increase of carrier mobility might be related to the activation of Mn2+ ions. Below the Curie temperature region, the activated Mn2+ ions will provide higher magnetic moments, and then the exchange interaction may increase in the material system. As a result, it will lead to enhance the spin-ordering effect and to reduce the probability of spin-disorder scattering. Therefore, the observation of gradual drop below the Curie temperature region in the temperature-dependent resistivity curve is expected to be a result from the spin-ordering effect due to the activation of Mn2+ ions.