Active dielectric metasurface based on phase‐change medium

By Cheng Hung Chu, Ming Lun Tseng, Jie Chen, P. Wu, Yi-Hao Chen, Hsiang‐Chu Wang, Ting-Yu Chen, W. Hsieh, H. Wu, Greg Sun and 1 more. 2016

376 citations recorded by the source corpus.

We propose all‐dielectric metasurfaces that can be actively re‐configured using the phase‐change material Ge2Sb2Te5 (GST) alloy. With selectively controlled phase transitions on the composing GST elements, metasurfaces can be tailored to exhibit varied functionalities. Using phase‐change GST rod as the basic building block, we have modelled metamolecules with tunable optical response when phase change occurs on select constituent GST rods. Tunable gradient metasurfaces can be realized with variable supercell period consisting of different patterns of the GST rods in their amorphous and crystalline states. Simulation results indicate a range of functions can be delivered, including multilevel signal modulating, near‐field coupling of GST rods, and anomalous reflection angle controlling. This work opens up a new space in exploring active meta‐devices with broader applications that cannot be achieved in their passive counterparts with permanent properties once fabricated.

Subfields: Aerospace Engineering, Atomic and Molecular Physics, and Optics, Electronic, Optical and Magnetic Materials

View Paper: https://www.semanticscholar.org/paper/99df9f07486a74cdc0e7dade6e9c4e10c5e1d20b