Carbonhagen 2021 - April 22, 10:00

You can look forward to two really exciting talks on Thursday – both are dealing with the extreme physics arising from extreme confinement, but in very different ways… and both are free upon registration.

The researcher who played a key role in the recent years fantastic breakthroughs in ultraconfined matter within 2D capillaries at University of Manchester, Radha Boya, will show us how the behavior of matter (ions, water, gas) is dramatically changed in narrow spaces. After that, one of the leading researchers within 2D nanophotonics, Rainer Hillenbrand, will shows us tricks of the light with phonon polaritons – the strange quasiparticles that describe the interaction between lattice vibrations and photons, and that open the door to manipulating light in surprising ways.

You can sign up here for Radha Boyas talk (https://forms.gle/Q8AaBPVYKZnoBpd27) and here for Rainer Hillenbrands talk (https://forms.gle/GZRzD1qtEgnrWzna9). IF you cannot access the registration forms let me know.

Abstracts are included below.

One atom thin capillaries: Confined water, Ion and Gas flows

Boya (2021 - April 22 - 10:00 CET, GMT+1) Register for talk here
Condensed Matter Physics Group, The University of Manchester and National Graphene Institute
Manchester M13 9PL, United Kingdom

It has been an aspiring goal to controllably fabricate nanopores and capillaries with dimensions approaching the size of small ions and water molecules. But surface roughness makes it challenging to produce capillaries with precisely controlled dimensions at this spatial scale. We have developed a method for fabrication of one atom thin, smooth angstrom (Å) scale capillaries through van der Waals assembly of two-dimensional (2D)-materials [1-5]. These capillaries can be envisaged as if individual atomic planes are removed from a bulk layered crystal leaving behind flat voids of a chosen height. A core strand of the work that I will present is the development of Angstrom-capillaries as a platform to probe intriguing molecular-scale phenomena experimentally, including: water flow under extreme atomic-scale confinement [5], complete steric exclusion of ions [3,5], voltage gating of ion flows [4] translocation of DNA [6], and specular reflection and quantum effects in gas reflections off a surface [2]. I will discuss and compare these gas flows to that in atomic-scale apertures, created from missing tungsten (W) sites in freestanding (WS2) monolayers, which show fast helium flow [7].

Nanophotonics with phonon polaritons in 2D materials

Hillenbrand (2021 - April 22 - 11:00 CET, GMT+1) Register for talk here
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.