Silicon Photonics at the Interface with a Phase Change Material

Phase change materials (PCMs) have the ability to control the phase [1], polarization [2], amplitude and coloration [3] of light. Examples of such materials are vanadium dioxide (VO
₂
), GeSbTe and AgInSbTe, which can, owing to changes in their refractive indices, alter the properties of light. Although PCMs have been studied in situations where light propagates from a low-index medium (e.g. air) into the material, there are more possibilities when total internal reflection is involved. In this paper, we investigate the interaction between light travelling in a dense medium with a phase change layer, with particular attention paid to interfaces involving silicon. The possibility of tuning and controlling light at the interface with silicon would be of interest for silicon photonics applications.