Size-dependent exchange bias in single phase Mn<sub>3</sub>O<sub>4</sub> nanoparticles

Size-dependent exchange bias in single phase Mn₃O₄ nanoparticles

Wang Song-Wei^{1, 2}, Zhang Xin^{1, 2, †,}, Yao Rong^{1, 2}, Rao Guang-Hui^{1, 2, ‡,}

(a) ZFC magnetization (MZFC) versus temperature under different fields for 60 nm Mn₃O₄. T_p represents the peak temperature. The inset shows ZFC and FC magnetization versus temperature under 100 Oe. (b) Temperature dependence of the ac susceptibility for different frequencies of 33 Hz, 133 Hz, 533 Hz, 1113 Hz at a driving ac field of 15 Oe for 60 nm Mn₃O₄. The inset shows logf versus log[(T_f − T_SG)/T_SG], demonstrating the agreement with Eq. (1). The solid line displays the best fitting result.