Rainer Hillenbrand: Nanophotonics with phonon polaritons in 2D materials

CARBONHAGEN 2021
Rainer Hillenbrand (2021 - April 22 - 11:00 CET, GMT+1)

CIC nanoGUNE BRTA
University of the Basque Country

Phonon polaritons - light coupled to optical lattice vibrations - in 2D materials exhibit ultra-short wavelengths, long lifetimes and strong field confinement, which allow for manipulating infrared light at the nanometer scale. Here, we discuss real-space nanoimaging studies of ultra-confined infrared phonon polaritons, essentially in thin hexagonal boron nitride layers and nanostructures, using scattering-type scanning near-field optical microscopy (s-SNOM) and nanoscale infrared Fourier transform (nano-FTIR) spectroscopy. We visualize and analyze phonon polaritons in nanoscale waveguides and resonators, as well as propagation with anomalous wavefronts when the (effective) in-plane permittivity of the 2D material is strongly anisotropic. Particularly, we will demonstrate that phonon polaritons can be utilized to achieve vibrational strong coupling with nanoscale amounts of organic molecules.