Topological photonics: Novel transport phenomena and topological lasers

The rapidly growing field of topological photonics exploits
non-trivial topology of the band structure of designed optical media to
control the behavior of light. Topological protection of photons leads to
highly unusual phenomena such as backscattering-immune transport and
robustness against disorders which hold great promise for applications as
well as exploration of fundamental theoretical concepts such as Berry
phase and topological invariants.
In this talk, I will showcase our groundbreaking achievement: the
introduction of the first topological quantum cascade laser operating in
the terahertz regime. Topological protection of lasing modes allows for
unprecedented robustness, compactness, versatile cavity designs, and
scalability.
Furthermore, I will delve into our exploration of novel transport
phenomena within Weyl semimetals where we show how the transport of bulk
states is influenced by the topological edge states. I will also discuss
our research on disordered topological systems.
The talk concludes by unveiling the uniqueness of photonic systems and the
promising future prospects of its synergistic integration with emergent
quantum materials, exemplified by van der Waals heterostructures.