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. Dynamic metasurfaces, whose properties change in time, are commonly referred to as time-varying or parametric metasurfaces. 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 illustrate the potential of tunable metasurfaces, leveraging phase change materials like vanadium dioxide, for applications such as terahertz bolometric detection systems and modulators. I will then show how the integration of metasurfaces with micro-electro-mechanical systems can improve spectrally tunable band-pass filters for infrared imaging and sensing devices. Following this, I will touch upon the use of metasurface filters in biomedical fiber sensing. Lastly, I will discuss my recent theoretical and experimental advances in parametric metasurfaces employing split-ring resonators with integrated varactor diodes. These metasurfaces demonstrate amplification and frequency upconversion in the microwave range, offering a promising route toward high-frequency applications enabled by ultrafast modulation.