Work Description

Date: 3 June, 2025

Dataset Title: Publically available repository for "Polariton Chern Bands in 2D Photonic Crystals beyond Dirac Cones"

Dataset Contact: Hui Deng [email protected]

Dataset Creators:
Name: Xin Xie
Email: [email protected]
Institution: University of Michigan Michigan Institute for Data & AI in Society
University of Michigan Department of Physics

Name: Kai Sun
Email: [email protected]
Institution: University of Michigan Department of Physics

Name: Hui Deng
Email: [email protected]
Institution: University of Michigan Department of Physics

Funding: W911NF-25-1-0055 (Army Research Office), FA2386-21-1-4066 (Air Force Office of Scientific Research),DMR 2132470(NSF),N00014-21-1-2770(Office of Naval Research),GBMF10694(Gordon and Betty Moore Foundation).

Key Points:
• Beyond-Dirac Topology: Identified two broadly accessible photonic crystal band structures—symmetry-protected bound states in the continuum (BICs) and quadratic-touching bands at the Γ point—as versatile platforms for realizing polariton Chern bands. These modes offer direct optical access and expand the design space beyond conventional Dirac-cone-based systems.
• High Chern Numbers and Tunable Topology via BICs: Demonstrated that BIC-based systems support polariton bands with high Chern numbers and allow flexible control of topological features through excitonic and photonic design.
• Experimentally Realizable Design with Large Gap and Chiral Edge States: Demonstrated >10 meV topological gaps and chiral edge states in simulated 2D PhC–transition metal dichalcogenide (TMD) systems.

Research Overview:
Polaritons, formed by strong light-matter interactions, open new avenues for studying topological phases, where the spatial and time symmetries can be controlled via the light and matter components, respectively. However, most research on topological polaritons has been confined to hexagonal photonic lattices featuring Dirac cones at large wave numbers. This restricts key topological properties and device performance, including sub-meV gap sizes that hinder further experimental investigations and future applications of polariton Chern insulator systems. In this study, we move beyond the traditional Dirac cone framework and introduce two alternative band structures in photonic crystals (PhCs) as promising platforms for realizing polariton Chern bands: bands with symmetry-protected bound states in the continuum and bands with symmetry-protected degeneracies at the Γ points. These band structures are prevalent in various PhC lattices and have features crucial for experimental studies. We show examples of higher Chern number bands, more uniform Berry curvature distributions, and experimentally feasible systems capable of achieving topological gap greater than 10 meV. Our findings show the broad applicability of polariton Chern bands in 2D PhCs and provide design principles for enhancing the functionality and performance of topological photonic devices, opening up exciting possibilities for better understanding and using topological physics.

Methodology:
MATLAB and Mathematica were used to calculate the eigenvalues and eigenvectors of the effective Hamiltonian, as well as the corresponding Berry curvature. Lumerical Finite Difference Time Domain (FDTD) simulations were employed to compute the band structures of both photonic and polariton modes in TMD–photonic crystal systems, along with the dispersion and mode profiles of the edge states.

Files contained here:

o Each folder corresponds to a figure included in the associated paper, with the first two characters of each folder name indicating the figure (e.g. f1 refers to Figure 1).

o Each folder contains: The MATLAB script (.m) to calculate the data (.mat) and plot the subfigures (.png) for each figure (.pdf & .pptx) in the main text.

o Figure 5: The raw and source data from FDTD simulations are saved and plotted in OriginLab project files (.opju).

o Figure 6: The raw and source data from FDTD simulations are saved as .txt and .xlsx files. MATLAB scripts (.m) are provided to plot the subfigures.

Related publication(s):
Xie, Xin, Sun, Kai, Deng, Hui. Polariton Chern Bands in 2D Photonic Crystals beyond Dirac Cones. Phys. Rev. X, 15(2), 021061 (2025). https://doi.org/10.1103/PhysRevX.15.021061

Use and Access:
This data set is made available under a Attribution-NonCommercial 4.0 International (CC BY-NC 4.0).

To Cite Data:
Xie, X. Publically available repository for "Polariton Chern Bands in 2D Photonic Crystals beyond Dirac Cones" [Data set], University of Michigan - Deep Blue Data. https://doi.org/10.7302/btbs-bb98