Screening-Induced Phase Transitions in Core-Shell Ferroic Nanoparticles

TL;DR

This study investigates how tunable screening shells affect phase transitions and polarization in core-shell ferroic nanoparticles of various shapes, with implications for nonvolatile memory applications.

Contribution

It introduces a theoretical framework analyzing screening effects in core-shell ferroic nanoparticles with shape-dependent phase behavior.

Findings

Shell screening length critically influences phase transitions.

Tunable shells enable control over the nanoparticle's polar state.

Results are relevant for designing nonvolatile memory devices.

Abstract

Using the Landau-Ginzburg-Devonshire approach, we study screening-induced phase transitions in core-shell ferroic nanoparticles for three different shapes: an oblate disk, a sphere, and a prolate needle. The nanoparticle is made of a ferroic CuInP2S6 core and covered by a "tunable" screening shell made of a phase-change material with a conductivity that varies as the material changes between semiconductor and metallic phases. We reveal a critical influence of the shell screening length on the phase transitions and spontaneous polarization of the nanoparticle core. Since the tunable screening shell allows the control of the polar state and phase diagrams of core-shell ferroic nanoparticles, the obtained results can be of particular interest for applications in nonvolatile memory cells.