Rabi Splitting in a Plasmonic Nanocavity Coupled to a WS 2 Monolayer at Room Temperature

Polaritons, resulting from the hybridization of light with polarization charges formed at the boundaries between media with positive and negative dielectric response functions, can focus light into regions much smaller than its associated free‐space wavelength. This property is paramount for a plethora of applications in nanophotonics, ranging from biological sensing to photocatalysis to nonlinear and quantum optics. In the two‐dimensional (2D) limit, represented by atomically thin and van der Waals (vdW) materials of single‐layers bound by weak vdW attraction, polaritons are characterized by extremely small wavelengths associated with extreme optical confinement, and furthermore can exhibit long lifetimes, electrical tunability, and extreme sensitivity to their dielectric environment, among many other desirable qualities in nano‐optical device applications. Here, the fundamentals of polaritons in atomically thin materials are summarized, emphasizing plasmon and exciton polaritons, their strong light–matter interactions, and nonlinear plasmonics. More specifically, this review opens with a pedagogical discussion of plasmons in extended and nanostructured graphene, providing a classical electrodynamical model in a nonretarded theoretical framework, and the ultraconfined acoustic plasmons supported by hybrid graphene–dielectric–metal structures. In addition, the basic principles are introduced and the recent developments on nonlinear graphene plasmonics and on strong coupling physics with atomically thin transition metal dichalcogenides are reviewed. Finally, potentially new, promising research directions in the burgeoning field of 2D nanophotonics are identified.

Section: Strong Light–matter Interactions In Layered Transition Metalmentioning

confidence: 99%

Strong Light–Matter Interactions Enabled by Polaritons in Atomically Thin Materials

Gonçalves

Stenger

Cox

et al. 2020

“…Plasmonic cavities also have different configurations, commonly formed by mirrors and plasmonic nanostructures . As shown in Figure e, TMD atomic layers with different thicknesses are placed inside the cavity formed between gold nanoparticles and a gold mirror (a similar approach is used by Han et al). The strong plasmonic field confined inside such a cavity couples strongly with excitons to form hybrid PEPs.…”

Section: Far‐field Spectroscopy Studies Of Eps In Tmdsmentioning

confidence: 99%

Recent Progress on Exciton Polaritons in Layered Transition‐Metal Dichalcogenides

Fei

2019

Exciton polaritons (EPs) are half‐light, half‐matter quasiparticles formed due to the coupling between photons and excitons in semiconductors. Their uniqueness lies at the strong light–matter interactions and long‐distance transport, thus promising for many novel applications in photonics, information, and quantum technologies. Recently, EPs in group‐VI transition‐metal dichalcogenides (TMDs) have attracted a lot of research interest due to their room‐temperature stability, long‐distance propagation, and controllability through electric gating, valley‐selective optical pumping, and precise thickness control. In this progress report, recent studies of EPs in TMDs are reviewed, highlighting their key properties and functionalities, and then discussing the potential directions for future research.

Section: Polaritons In 2d Materialsmentioning

confidence: 99%

“…By changing the diameter of Ag nanodisks, the LSPR can be either in resonance or out of resonance with MoS 2 excitons, which effectively tunes the plasmon–exciton coupling strength. X. Han et al investigated the strong coupling between WS 2 monolayer exciton and individual Ag nanocubes instead of the aforementioned plasmonic lattices . The structure was fabricated by successively depositing silver and Al 2 O 3 thin films on top of a silicon substrate, and then transferring the WS 2 monolayer and finally drop‐casting Ag nanocubes.…”

Section: Polaritons In 2d Materialsmentioning

confidence: 99%

“…X. Han et al investigated the strong coupling between WS 2 monolayer exciton and individual Ag nanocubes instead of the aforementioned plasmonic lattices. [179] The structure was fabricated by successively depositing silver and Al 2 O 3 thin films on top of a silicon substrate, and then transferring the WS 2 monolayer and finally drop-casting Ag nanocubes. The schematic of the structure, as well as bright-field and dark-field images, are shown in the left panels of Figure 10d.…”

Section: Wwwadvopticalmatdementioning

confidence: 99%

See 1 more Smart Citation

Polariton Photonics Using Structured Metals and 2D Materials

Cai

Wang

et al. 2019

Polaritons are quasiparticles originating from strong interactions between photons and elementary excitations that could enable high tunability, tight electromagnetic field confinement, and large density of photonic states, making it possible to achieve novel and otherwise inaccessible functionalities. For these reasons, polaritons spawn great interest in the fields of physics, materials science, and optics for both fundamental studies as well as potential applications (e.g., modulators, photodetectors, photoluminescence, etc.). In recent years, the explosive growth of research in graphene and other 2D van der Waals materials is witnessed because they provide a new platform that substantially complements conventional metals, dielectrics, and semiconductors to investigate different polariton modes. This review highlights the works published in recent years on the topic of polariton photonics based on structured metals, graphene, and transition‐metal dichalcogenides (TMDs). The exotic optical properties of the polaritons in metallic structures and 2D van der Waals materials offer bright prospects for the development of high‐performance photonic and optoelectronic devices.