Strong light-matter coupling; from self-hybridized polaritons to Casimir self-assembly

Timur Shegai Chalmers University

Strong light-matter interactions are at the core of many electromagnetic phenomena. In this talk, I will give an overview of several nanophotonic systems which support polaritons – hybrid states of light and matter, as well as try to demonstrate their potential usefulness in applications. I will start with transition metal dichalcogenides (TMDs) and specifically discuss one-dimensional edges in these two-dimensional materials [1-2]. I will also discuss the concept of self-hybridization, a scenario in which both light and matter subparts in a polaritonic system are supported by the same (nano)structured material [1-4]. We have recently demonstrated such self-hybridization in TMD nanostructures [1-4] and levitating water droplets [4-5]. The latter is interesting, due to abundance of water droplets in natural systems, including mists, fogs, and clouds. Furthermore, I will show that Fabry-Pérot resonators, one of the most important workhorses of nanophotonics, can spontaneously form in an aqueous solution of gold nanoflakes [6-8]. This eLect is possible due to the intricate balance between attractive Casimir-Lifshitz forces and repulsive electrostatic forces acting between the flakes. There is a hope that this technology is going to be useful for future developments in self-assembly and polaritonics, as well as help develop a unified view of Casimir and strong light-matter coupling phenomena.

[1] Nat. Commun., 11, 4604, (2020)

[2] Laser & Photonics Rev., 17, 2200057, (2023)

[3] Nat. Photon., 18, 751-757, (2024)

[4] J. Chem. Phys., 154, 024701, (2021)

[5] Phys. Rev. Lett., 132, 193804, (2024)

[6] Nature, 597, 214-219, (2021)

[7] Nat. Phys., 19, 271-278, (2023)

[8] Sci. Adv., 10, eadn1825, (2024)