Spin glass behavior and negative magnetization in Co2Sn1-xTixO4 (0≤x≤0.9)

We have investigated the nature of the magnetic properties of cobalt-based inverse spinel oxides Co2Sn1-xTixO4 (0 <= x <= 0.9) employing comprehensive magnetic measurements. As the substitution of Ti ions for Sn ions increases, the DC magnetization measurement in the field cooled (FC) processes shows that negative magnetization behavior. The magnetization curves exhibit a compensation temperature T-comp (defined by the temperature of M-ZFC = M-FC = 0), which can be attributed to the magnetization of two sublattices (A and B sites) balance each other. Interestingly, the spin-glass (SG) and the large exchange bias (EB) behavior were observed in the Co2Sn1-xTixO4 systems at low temperatures. Besides, the values of H-EB exhibit strong frequency and temperature dependence. Furthermore, the origin of SG behavior in the Co2Sn1-xTixO4 system can be attributed to the dilution effect of Ti resulting in atomic disorder. The large exchange anisotropy may result from the magnetic unidirectional anisotropy at the ferromagnetic/SG interface. On the other hand, this large exchange bias behavior also is attributed to the atomic disorder in the system. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The cobalt-based inverse spinel oxides Co2Sn1-xTixO4 exhibit negative magnetization behavior and compensation temperature phenomenon, as well as spin-glass and large exchange bias behavior at low temperatures. The dilution effect of Ti and atomic disorder lead to the SG behavior and large exchange anisotropy in the system.