# Emerging Device Applications From Strong Light–Matter Interactions in 2D Materials

## TL;DR

This review explores how 2D materials with strong light-matter interactions can be used to create compact, efficient optoelectronic devices like solar cells and LEDs for future on-chip technologies.

## Contribution

The paper provides a focused review on device architectures and integration strategies for 2D material-based optoelectronics using excitons and polaritons.

## Key findings

- 2D materials enable low-threshold lasing and ultrafast modulation through strong coupling with cavity photons.
- Design strategies for solar cells and photodetectors leverage exciton-polariton systems for improved performance.
- On-chip integration of all-2D material LEDs is a promising path for next-generation photonic circuits.

## Abstract

Two‐dimensional (2D) semiconductors provide a powerful platform for highly compact optoelectronic devices, spanning solar cells, photodetectors, light‐emitting diodes (LEDs), and lasers. In these materials, tightly bound excitons dominate key metrics such as absorption strength, quantum efficiency, response speed, and spectral purity. When driven into the strong light–matter coupling regime, excitons hybridize with cavity photons, plasmons, or magnons to form exciton‐, plasmon‐, and magnon‐polaritons, enabling engineered dispersion, low‐threshold lasing, ultrafast modulation, and enhanced nonlinear functionality within footprint‐limited architectures. Earlier reviews have focused on the fundamentals of strong coupling, band engineering, and realizing strong coupling with a variety of 2D materials. In this review, we will discuss different device architectures based on exciton and polaritons‐based systems, integrating 2D materials and heterostructures with dielectric cavities, metasurfaces, waveguides, and hybrid metal/2D magnet platforms. We emphasize design strategies based on the best figures of merit for solar cells, photodetectors, and lasers from exciton‐ and polariton‐based systems. Finally, we will discuss the routes to on‐chip integration of LEDs from all‐2D materials‐based devices for next‐generation photonic integrated circuits. Further, we will discuss advanced electron microscopy and nano‐imaging to map polaritonic fields and exciton distributions, linking nanoscale coupling to macroscopic device behavior and outlining a roadmap for next‐generation exciton/polariton devices.

Two‐dimensional semiconductors enable extremely compact optoelectronic devices such as solar cells, sensors, LEDs, and lasers. Their strong light–matter interactions allow efficient light emission, detection, and energy conversion. This review article discusses the recent progress in integrating these materials with optical cavities and nanostructures to achieve low‐power, fast, and scalable photonic devices, paving the way for next‐generation on‐chip optical technologies.