# Scaling of the Electrical Conductivity Spectra Reveals Distinct Transport Responses in A2SmTaO6 [A = Ba, Sr, Ca]

## TL;DR

This study investigates how microstructural inhomogeneities in A2SmTaO6 double perovskites influence electrical conduction and relaxation behaviors, revealing distinct transport responses through scaling of conductivity spectra.

## Contribution

It demonstrates the impact of microstructural disorder on conduction mechanisms and relaxation timescales in A2SmTaO6 materials using scaling analysis of electrical spectra.

## Key findings

- Scaling of conductivity spectra reveals correlation between conduction and relaxation.
- Microstructural inhomogeneities restrict universality of conduction mechanisms.
- Disorder influences charge carrier hopping and relaxation processes.

## Abstract

Disorder plays an important role in materials science, influencing material behavior across different length scales. Imperfections like vacancies, atomic substitutions, lattice distortions, and microstructural inhomogeneities, disrupt ideal periodicity thereby altering physical properties. Analogous to spin-glass systems, electrical 'glassiness' arises when charge carriers confront disordered energy landscapes, leading to a broad range of relaxation times, especially in polycrystalline materials where dipoles experience competing exchange interactions. Complex impedance, permittivity, and electric modulus distill out separate resistive and capacitive effects, offering insights into how microstructural inhomogeneities affects conduction mechanism. In polycrystalline double perovskites A2SmTaO6 (A = Ba, Ca), with a power law driven ac conductivity, the hopping and relaxation of carriers is affected by both grains and grain boundaries. Scaling of ac conductivity and impedance response reveals correlation between conduction and relaxation timescales. The inhomogeneities in local energy landscape of 'frustrated' dipoles restrict the 'universality' of conduction mechanism across the bulk length scale.