(she/her/hers)
Harvard University
optics, nanophotonics, flat optics, metasurfaces
Christina is a PhD candidate in Applied Physics at Harvard University, working in the group of Professor Federico Capasso. Previously, she received her Bachelor's degree in Physics from the University of Heidelberg in Germany. Her research focuses on controlling the interaction of light and matter on the nanoscale to design novel nanophotonic devices. Christina has received several fellowships including the Meta PhD fellowship.
Flat optics based on metasurfaces: structuring light on the nanoscale
When it comes to optical building blocks, conventional optics like lenses reach their limit for miniaturization in the range of multiple wavelengths as they are based on light refraction and propagation. My work focuses on controlling the interaction of light and matter on the nanoscale, intending to further explore the properties of structured light and to create novel nanophotonic devices such as compact holographic AR/VR systems, light sources, and detectors.
Promising platforms for this control are metasurfaces, 2D-arrays of nanoscale light scatterers, that have proven capable of engineering the properties of light (i.e., intensity, phase, polarization) on the nanoscale and therefore pave the way to ultra-thin and light-weighted optical devices. Furthermore, metasurfaces allow for light control exceeding the limits of conventional optical elements (e.g., negative refractive index). We aim to use this advanced control to explore novel effects in structured light such as topologically protected polarization singularities.
In recent years I additionally got interested in using metasurfaces to feedback and control emitting systems. For instance, we recently demonstrated a wavelength-tunable external cavity laser with arbitrary output control, where a single multi-function metasurface simultaneously served as feedback for the gain medium and controlled the emitted wavefront. In general, due to the versatility of metasurfaces, the interaction of emitting systems with cavities formed by reflective metasurfaces promises compact systems capable of influencing the wavelength, power, polarization, and shape of the emitted wavefront while keeping the complexity of the system to a minimum.