Magnetic properties of spin frustrated spinel ZnFe2O4/ZnCr2O4 superlattices

Superlattice films composed of frustrated spin systems, [ZnFe2O4](m)/[ZnCr2O4](m), are grown on MgAl2O4 (111) substrates by pulsed laser deposition, and their frustrated magnetism is studied. The superlattice films show spin-glass behavior and the spin-glass transition temperature (T-g) varies nonmonotonically as a function of the layer thickness m. T-g increases with decreasing m due to an increase in the inhomogeneous exchange interaction between Cr3+ and Fe3+ at the interface. However, below m = 4, a decrease in T-g is observed. Compared with the solid solution Zn(CrFe)O-4 film and the other superlattices, the decrease in T-g is considered to be a unique property of the periodically modulated short period superlattices. (C) 2015 AIP Publishing LLC.