Electron paramagnetic resonance and low-field microwave absorption in the manganese–gallium oxide

•We have investigated the microwave absorption in MnGa2O4 powders in 92–296 K temperature range.•EPR spectra suggest the presence of magnetic fluctuations that proceed to antiferromagnetic ordering at low temperature.•LFMA signal give also evidence of these magnetic fluctuations.

Microwave absorption measurements in MnGa2O4 powders are carried out at X-band (8.8–9.8 GHz) in 92–296 K temperature range. For all temperatures, the electron paramagnetic resonance (EPR) spectra show a single broad line due to Mn2+ ions. Temperature dependence of the EPR parameters: the peak-to-peak linewidth (ΔHpp), the integrated intensity (IEPR) and the g-factor, suggests the presence of magnetic fluctuations that precede to antiferromagnetic ordering at low temperature. Additionally, the low-field microwave absorption (LFMA) is used to give further information on this material, giving also evidence of these magnetic fluctuations.