Why care about half-light half-matter quasiparticles?

ABSTRACT

Strong exciton-photon interaction results in the formation of half-light half-matter quasiparticles called exciton-polaritons (EPs) that take on the properties of both its constituents. In this talk I will first introduce the concept of exciton-polariton formation in low-dimensional semiconductors. Following this, I will discuss our recent work on realizing magneto-EPs in van der Waals magnet - CrSBr and the possibility of controlling the magneto-optic response by tuning the light or matter fraction of the polariton states [1]. In addition to tuning the magneto-optic response, we will also show evidence of coupling between coherent magnons and polaritons through time resolved measurements where the fingerprint of GHz magnon oscillations is observed on the polariton states. I will also present our recent work on the role of magnons on nonlinear polariton interaction in CrSBr [2] as well as the demonstration of highly confined EPs [3].

In the second part of the talk, I will discuss the formation of out-of-equilibrium condensates at room temperature using polaritons formed using excitons in organic molecules [4,5].Time permitting, I will discuss approaches to create condensate lattices in such systems [6] and their potential application as Hamiltonian simulators will be briefly discussed.

[1] F. Dirnberger et al. Nature vol. 620, p. 533 (2023).

[2] B. Datta, P. Adak, S. Yu et al., Nature Materials vol. 24, p. 1027 (2025)

[3] P. Adak, S. Yu, J. Abad et al. ArXiv (2025)https://doi.org/10.48550/arXiv.2507.04367

[4] P. Deshmukh et al. ACS Photonics vol. 11, p. 348 (2024).

[5] D. Choi et al. Adv. Opt. Mat. vol. 13, 2500086b (2025)

[6] R. Yadav et al. Nano Letters vol. 24, p. 4945 (2024).

BIOGRAPHY

Vinod Menon is a Professor of Physics at the City College of New York and doctoral faculty at the Graduate Center of the City University of New York (CUNY). He is a fellow of the Optical Society of America (now Optica), The American Physical Society (APS), and an IEEE Distinguished Lecturer in Photonics (2018-2020). His current research interests include cavity QED with 2D materials and organic molecules, Hamiltonian simulators with light, and engineered nonlinear optical materials. More details about his group can be found at: https://lanmp.org/