Giant Nonlinear Response of Monolayer MoS₂ Induced by Optimal Field‐Enhancement Gain Mode on the Surface of Hyperbolic Metamaterials

Abstract

The electric field (EF) enhancements of resonant modes in metamaterials have been widely utilized to amplify optical response of 2D materials for advanced applications. However, for the vast majority of metamaterials, enhancing optical response of 2D materials by resonant modes seriously suffer from high loss, narrowband, and inside hot-spot (i.e., the region with strong EF enhancements). Here, the periodic hyperbolic metamaterials (PHMM) are proposed, which can provide intensive and broadband EF enhancement on top surface with low absorption, due to theirs specific hyperbolic dispersion and geometry characteristics. Moreover, it is revealed that there exists a broadband range (defined as the high field-enhancement gain (FEG) region), where nonlinear optical responses are stronger than those caused by the resonant mode. By integrating monolayer MoS 2 with the PHMM, it is demonstrated that the largest enhancement of second harmonic generation occurs at wavelength of the optimal FEG mode, being as high as 22 145-times with its conversion efficiency up to 1.1 × 10 −6 W −1 . The findings demonstrate giant nonlinear response of monolayer 2D materials, and establish an ideal platform for surface enhancement of light-matter interactions, opening a new way for metaoptics applications.

Ultrasensitive Refractive Index Sensing Based on Hybrid High-Q Metasurfaces

“…The FoM value up to 1431 in a wide RI range (1− 1.384) has been demonstrated by experimental measurements, verifying the excellent performance of RI sensing in photonic systems. Our findings not only present a powerful hybrid metasurface with great potential in constructing optical biosensors but also provide a constructive avenue for integrating the advantages of plasmonic and dielectric photonic systems, 29,30 guiding the design and fabrication of advanced photonic devices in the future.…”

Plexcitonic strong coupling: unique features, applications, and challenges

“…In 2018, Vaianella et al [270] investigated the strong coupling in gain-enhanced multilayered HMMs. It should be noted that since the external light can hardly interact with the photonic mode of HMM due to the mismatch of momentum [271], the dyes inside the HMM were pumped by internal light-cone, as presented in figure 18(d). Despite these HMMs with relatively large size, recently, Guo et al [272] theoretically proposed to construct a plexcitonic strong-coupling system with the hybridization of a hyperbolic nanorod (HNR) and the excitons of a molecule (serves as the QE).…”

Exfoliation Procedure-Dependent Optical Properties of Solution Deposited MoS2 Films

“…2c,d further illustrate the potential to engineer optical semiconducting TMDC excitonic behavior as a function of solution formulation and processing conditions. Representative optical phenomena that may be further manipulated via controlled exfoliation methodologies include near-field electromagnetic coupling (e.g., exciton-exciton, exciton-polariton, and plexcitons) 10,11,[57][58][59][60] , nonlinear optical effects 11,[61][62][63] , photoluminescence emission intensity 8,64 , and low-dimensional chiroptical effects 65 .…”