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.