Size effect of the Ge2Sb2Te5 cell atop the silicon nitride O-ring resonator on the attenuation coefficient

We have studied transmission spectra of a silicon nitride O-ring resonator with a Ge2Sb2Te5 (GST) thin-film cover. We have performed numerical simulations of the transmission, absorption, reflection, and scattering for the GST cells of various thicknesses and lengths and have also measured transmission spectra O-ring resonators for GST cells of various length and phase states. An analysis of the changes in the Q-factors has enabled us to identify the region of the GST cells where light scattering and absorption dominate and find the size dependence of amorphous and crystalline GST attenuation coefficients. The demonstrated results pave the way to high energy-efficient on-chip devices of a small footprint that can be switched either optically or electrically. (c) 2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). https://doi.org/10.1063/5.0066387

Automated summary

This study investigates the transmission spectra of a silicon nitride O-ring resonator with a Ge2Sb2Te5 (GST) thin-film cover, analyzing the region where light scattering and absorption dominate in the GST cells and finding the size dependence of amorphous and crystalline GST attenuation coefficients. The results pave the way for the design of high energy-efficient on-chip devices that can be switched optically or electrically in a small footprint.