Time-resolved temperature mapping leveraging the strong thermo-optic effect in phase-change devices

TL;DR

This paper introduces an experimental method using the thermo-optic effect in GST to achieve high-resolution, non-invasive, time-resolved temperature mapping of phase-change devices, aiding their rapid characterization.

Contribution

The authors develop a novel optical technique for spatial and temporal thermal measurements in phase-change materials, improving device characterization methods.

Findings

Excellent agreement between experimental measurements and simulations.

Enables rapid, non-invasive thermal characterization of phase-change devices.

Facilitates better understanding of thermal dynamics in phase-change applications.

Abstract

Optical phase-change materials are highly promising for emerging applications such as tunable metasurfaces, reconfigurable photonic circuits, and non-von Neumann computing. However, these materials typically require both high melting temperatures and fast quenching rates to reversibly switch between their crystalline and amorphous phases, a significant challenge for large-scale integration. Here, we present an experimental technique which leverages the thermo-optic effect in GST to enable both spatial and temporal thermal measurements of two common electro-thermal microheater designs currently used by the phase-change community. Our approach shows excellent agreement between experimental results and numerical simulations and provides a non-invasive method for rapid characterization of electrically programmable phase-change devices.