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Transport of elementary excitations is a fundamental property of two-dimensional (2D) semiconductors, essential for wide-ranging phenomena and device applications. Although exciton transport reported in 2D materials barely exceeds 1 to 2 micrometers, coherent coupling of excitons with photons to form polaritons enables extended transport lengths and offers opportunities to use photonic mode engineering for tailored transport. Conventional vertical cavity or waveguide polaritons, however, are challenging to tune and integrate into photonic circuits. We report the transport of transition metal dichalcogenide polaritons in 2D photonic crystals that are highly versatile for tuning, mode engineering, and integration. We achieve an order-of-magnitude enhancement in transport length compared to bare excitons and reveal transport dependence on polariton dispersion and population dynamics, which are controlled via photonic crystal design and pump intensity. Stimulated relaxation observed in the system suggests the potential for forming superfluid polaritons with frictionless transport. These findings establish 2D photonic crystal polaritons as a versatile platform for advancing photonic energy transport technologies.
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This content will become publicly available on December 4, 2025
Excitons and polaritons in two-dimensional transition metal dichalcogenides: a tutorial
Since the discovery of two-dimensional transition metal dichalcogenide monolayers as direct bandgap semiconductors with pronounced room-temperature exciton transitions, research on excitons and polaritons in these materials has exploded worldwide. Here, we give an introductory tutorial on the basic properties of excitons and polaritons in these materials, emphasizing how they are different from those in conventional semiconductors, and discuss some of the most exciting new phenomena reported.
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- Award ID(s):
- 2004287
- PAR ID:
- 10638671
- Publisher / Repository:
- Optica
- Date Published:
- Journal Name:
- Advances in Optics and Photonics
- Volume:
- 16
- Issue:
- 4
- ISSN:
- 1943-8206
- Page Range / eLocation ID:
- 1064
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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