Integration of two-dimensional materials in optical systems: towards nonlinear waveguides, integrated quantum light sources, and polariton physics

Physikalisches Kolloquium

Speaker:

Falk Eilenberger

Date:

20/05/2022 15:45

Where:

Otto-Lehman-Hörsaal and Zoom

Affiliation:

Friedrich-Schiller-Universität Jena

Host:

Prof. Dr. Carsten Rockstuhl

Abstract

Monolayer materials are a natural addition to the set of optical materials and can be used to
functionalize classic micro- and nanooptical systems. Moreover, they grow in a crystalline manner on
many substrates and structures, irrespective of epitaxial compatibility, which allows for scalable integration
with many optical systems. I will discuss some strategies which can be used to integrate 2D-materials with
coatings, resonators, and waveguides, without massively degrading their properties.
From an optics point-of-view transition-metal dichalcogenides (TMCs) and hexagonal Boron-Nitride (hBN)
are particularly appealing material classes. TMCs are direct semiconductors with bandgaps in the visible.
They exhibit unusually high refractive indices, strong and highly sensitive fluorescence, and large
nonlinear coefficients. hBN, on the other hand, is a large bandgap dielectric, with stable, room-temperature
single-photon emitters.
Based on the established materials platform and integration techniques I shall discuss nanoscale light
sources, based on polaritonic lasing and one-dimensional p-n-junctions. Another topic is the integration of
2D-materials with optical fibers and nanophotonic waveguides. These waveguides enhance light-matter
interaction and enable sensing applications and new pathways to fiber-based nonlinear optics. Moreover,
I will discuss single photon emitters in hBN and argue that they are not only suitable for miniature and
space-compatible QKD-devices but that they enable new applications in optical sensing, such as a highly
sensitive test of Born’s rule.