Exploring Giant Dielectric Constant in Dy2CoMnO6: Evidence of Non-Overlapping Small Polaron Hopping

Abstract Perovskites, both natural and synthetic, form a large class of materials are a vast class of materials with significant tech nological relevance due to their remarkable physical properties, such as superconductivity, magnetoresistance, ionic
conductivity, and diverse dielectric behaviors. In this study, the dielectric relaxation and transport properties of the
double perovskite Dy2CoMnO6 (DCMO) synthesized via high-energy ball milling are investigated. DCMO exhibits
a notably large dielectric constant, attributed to a combination of intrinsic and extrinsic mechanisms. Frequency dependent dielectric studies reveal non-Debye-like behavior, validated by augmented Havriliak–Negami function fit ting. Impedance spectroscopy confirms the semiconducting nature of DCMO, showing a negative temperature co efficient of resistance, and identifies two distinct relaxation processes corresponding to grain boundaries and grain
interiors thereby highlighting the impact of microstructure and defects. The Cole-Cole plot further supports the non Debye behavior, while thermally activated relaxation suggests damped charge carrier dynamics at grain boundaries.
Conduction analysis using augmented Jonscher’s power law reveals non-overlapping small polaron tunneling as the
dominant mechanism driving both the dielectric response and transport properties, with DC conductivity suggesting
a three-dimensional variable range hopping model. These results provide significant insights into the dielectric and
transport properties of DCMO, highlighting its promising potential for advanced electronic applications.