Event
AMOLF Colloquium
Public colloquium
- Speaker: Dr. Sander Mann (UvA)
- Title: How advanced materials are rewriting the rules of thermal radiation
- Abstract: The way objects absorb and emit heat as thermal radiation is governed by Kirchhoff’s law, which dictates that objects absorb and emit equally well at each wavelength and angle. In recent years, however, novel materials such as metamaterials that twist light, break symmetries, or change in time have been challenging and expanding this law in surprising ways.
- In this talk, we will explore how Kirchhoff’s law applies or needs to be extended for these materials. We experimentally test this for surfaces that radiate circularly polarized light, confirming a modern version of Kirchhoff’s law that accounts for polarization. Extending on this platform, we demonstrated a fully thermal hologram: a metasurface that when heated up generates a hologram – without any external illumination. Finally, we explore nonreciprocal and time-varying materials and show that, even here, a generalized form of Kirchhoff’s law allows us to predict emission based on absorption, which is often much easier to obtain. Together, these insights offer powerful tools to design and understand thermal emission in next-generation materials and technologies.
Small Colloquium
- Speaker: Paul Baconnier
- Title: Memories and motifs in massively multistable materials
