Effect of gamma radiation on the structural, dielectric and magnetoelectric properties of nanostructured hexagonal YMnO3

• Multiferroic YMnO3 nanoparticles have been synthesized by using the sol–gel method.
• Effect of γ-irradiation on the physical and structural properties of the samples is investigated.
• γ-Radiation results significant change on the dielectric constant and magnetoelectric coefficient.

Nanocrystalline YMnO3 ceramic powders have been synthesized by using the standard sol–gel method. The samples were irradiated with 60Co γ-radiation at a dose rate of 4.7 kGy/h for different time intervals. The effects of irradiation on surface morphology viz. grain size, porosity and also the existence of a few impurity phases have been studied by scanning electron microscopy, X-ray diffraction and far-infrared reflectivity spectroscopy. Irradiation in air produced changes in the dielectric spectrum in the frequency range between 100 Hz and 2 MHz. Subjection of γ-radiation brings about key change on the properties as a consequence of structural transformations. The attained data shows that the electrical conductivity and dielectric constant is actually so much dependent on radiation dose. A quantitative magnetoelectric coefficient measurement in YMnO3 nanosystem was performed by using the dynamic lock-in amplifier technique. The response of the magneto-electric coefficient shows perfect anisotropy in the irradiated samples.