Metasurfaces are flat analogues of metamaterials, they are artificial composite materials made of resonant inclusions (also called meta-atoms) that are smaller than the wavelength of electromagnetic waves of interest. Dynamic tuning of metamaterials represents an active area of research, holding the promise of being the next breakthrough in their evolution. Metasurfaces, whose characteristics vary temporally, are commonly referred to as time-varying  or parametric. They offer opportunities to overcome fundamental limitations in electromagnetics and realise effects previously unattainable with conventional metamaterials, such as magnetic-free nonreciprocity. With higher modulation speeds, complete control over light in both space and time becomes achievable.

In this talk, I will delve into my research findings on dynamic metasurfaces. I will first introduce parametric metasurfaces based on split-ring resonators with integrated varactor diodes, which can be used to amplify and upconvert electromagnetic waves in the microwave and sub-terahertz frequency ranges. Following this, I will illustrate the potential of tunable metasurfaces, leveraging phase change materials like vanadium dioxide, for applications such as terahertz bolometric detection systems. I will then show how the integration of metasurfaces with micro-electro-mechanical systems can improve spectrally tunable band-pass filters for infrared imaging devices. Lastly, I will touch upon the use of metasurface filters in biomedical fiber sensing.

Zoom link

https://anu.zoom.us/j/86292244335?pwd=VWhMcjR5RkExeVhBOW0ybUJrVVM4QT09