Center for Functional Nanomaterials Seminar

In low-dimensionality objects such as nanowires and nanoparticles, material properties are drastically influenced by confinement effects. New physics rules the electronic and optical properties, which make designing and understanding nanomaterials so complex yet so appealing. For example, nanotube forests exhibit unique thermionic properties, and nanoparticles' optical response changes drastically with their size and surface chemistry. Understanding and tuning those effects is the key to designing nanoparticles and nanowires for applications such as quantum computing, solar cells and water treatment. Because characterizing such phenomena requires a combination of energy, momentum and spatial resolution, it remains extremely challenging.

During this presentation, we will discuss how to probe optical and quantum effects in a scanning transmission electron microscope through the use of momentum-resolved electron energy loss spectroscopy and cathodoluminescence. We will also see how light injection can be combine with such techniques to study operando energy conversion and other photo-induced effects. Finally, we will discuss how to overcome the challenges associated with adapting those methods to electron-beam sensitive samples such as soft and biological nanomaterials.