Elasticity-driven Nanoscale Texturing in Complex Electronic Materials

TL;DR

This paper introduces a Ginzburg-Landau model to simulate nanoscale textures in complex electronic materials, revealing how elastic interactions and doping induce rich, multiscale inhomogeneities relevant to materials like manganites and cuprates.

Contribution

The paper develops a novel simulation model demonstrating how elastic compatibility and doping create complex, multiscale textures in electronic materials, advancing understanding of their inhomogeneous states.

Findings

Nanoscale phase separation observed in simulations

Elastic fields induce mesoscale inhomogeneities

Textures depend on doping, stress, and temperature

Abstract

Finescale probes of many complex electronic materials have revealed a non-uniform nanoworld of sign-varying textures in strain, charge and magnetization, forming meandering ribbons, stripe segments or droplets. We introduce and simulate a Ginzburg-Landau model for a structural transition, with strains coupling to charge and magnetization. Charge doping acts as a local stress that deforms surrounding unit cells without generating defects. This seemingly innocuous constraint of elastic `compatibility', in fact induces crucial anisotropic long-range forces of unit-cell discrete symmetry, that interweave opposite-sign competing strains to produce polaronic elasto-magnetic textures in the composite variables. Simulations with random local doping below the solid-solid transformation temperature reveal rich multiscale texturing from induced elastic fields: nanoscale phase separation, mesoscale intrinsic inhomogeneities, textural cross-coupling to external stress and magnetic field, and temperature-dependent percolation. We describe how this composite textured polaron concept can be valuable for doped manganites, cuprates and other complex electronic materials.