Dielectric breakdown by electric-field induced phase separation

TL;DR

This paper demonstrates how electric-field induced phase separation can dramatically increase conductivity in materials, enabling control over dielectric properties for applications like neuromorphic computing and batteries.

Contribution

It reveals that tuning electric fields in systems with variable permittivity and conductivity induces filament formation, leading to large conductivity changes, a novel insight for device engineering.

Findings

Electric fields can induce filament-like conductive domains.

Conductivity varies by orders of magnitude with electric field tuning.

Applicable to neuromorphic devices and Li-ion batteries.

Abstract

The control of the dielectric and conductive properties of device-level systems is important for increasing the efficiency of energy- and information-related technologies. In some cases, such as neuromorphic computing, it is desirable to increase the conductivity of an initially insulating medium by several orders of magnitude, resulting in effective dielectric breakdown. Here, we show that by tuning the value of the applied electric field in systems { with variable permittivity and electric conductivity}, e.g. ion intercalation materials, we can vary the device-level electrical conductivity by orders of magnitude. We attribute this behavior to the formation of filament-like conductive domains that percolate throughout the system, { which form only when the electric conductivity depends on the concentration}. We conclude by discussing the applicability of our results in neuromorphic computing devices and Li-ion batteries.