Abstract The tunability of the bandgap, absorption and emission energies, photoluminescence (PL) quantum yield, exciton transport, energy transfer in transition metal dichalcogenide (TMD) monolayers provides a new class functions for wide range ultrathin photonic devices. Recent strain‐engineering approaches have enabled to tune some these properties, yet dynamic control at nanoscale with real‐time ‐space characterizations remains challenge. Here, nano‐mechanical naturally‐formed wrinkles...

Abstract Emerging photo-induced excitonic processes in transition metal dichalcogenide (TMD) heterobilayers, e.g., interplay of intra- and inter-layer excitons conversion to trions, allow new opportunities for ultrathin hybrid photonic devices. However, with the associated large degree spatial heterogeneity, understanding controlling their complex competing interactions TMD heterobilayers at nanoscale remains a challenge. Here, we present an all-round dynamic control interlayer-excitons...

Abstract Photoluminescence (PL), a photo-excited spontaneous emission process, provides wealth of optical and electronic properties materials, which enable microscopic spectroscopic imaging, biomedical sensing diagnosis, range photonic device applications. However, conventional far-field PL measurements have limitations in sensitivity spatial resolution, especially to investigate single nano-materials or nano-scale dimension them. In contrast, tip-enhanced photoluminescence (TEPL)...

Understanding and controlling the nanoscale transport of excitonic quasiparticles in atomically thin two-dimensional (2D) semiconductors are crucial to produce highly efficient nano-excitonic devices. Here, we present a nanogap device selectively confine excitons or trions 2D transition metal dichalcogenides at nanoscale, facilitated by drift-dominant exciton funneling into strain-induced local spot. We investigate spatiospectral characteristics funneled WSe2 monolayer (ML) converted MoS2 ML...

The generation of high-purity localized trions, dynamic exciton-trion interconversion, and their spatial modulation in two-dimensional (2D) semiconductors are building blocks for the realization trion-based optoelectronic devices. Here, we present a method all-optical control exciton-to-trion conversion process its distributions MoS2 monolayer. We induce nanoscale strain gradient 2D crystal transferred on lateral metal-insulator-metal (MIM) waveguide exploit propagating surface plasmon...

Exciton-polaritons confined in plasmonic cavities are hybridized light-matter quasiparticles, with distinct optical characteristics compared to plasmons and excitons alone. Here, we demonstrate the electric tunability of a single polaritonic quantum dot operating at room temperature electric-field tip-enhanced strong coupling spectroscopy. For nanoplasmonic tip cavity variable dc local field, dynamically control Rabi frequency corresponding polariton emission, crossing weak coupling. We...

Abstract In atomically thin semiconductors, localized exciton (X L ) coupled to light provides a new class of optical sources for potential applications in quantum communication. However, most studies, X photoluminescence (PL) from crystal defects has mainly been observed cryogenic conditions because their sub‐wavelength emission region and low yield at room temperature. Hybrid‐modality cavity‐spectroscopy induce probe the emissions nanoscale semiconductors is presented. By placing WSe 2...

Abstract Spatial manipulation of excitonic quasiparticles, such as neutral excitons, charged and interlayer in two-dimensional semiconductors offers unique capabilities for a broad range optoelectronic applications, encompassing photovoltaics, exciton-integrated circuits, quantum light-emitting systems. Nonetheless, their practical implementation is significantly restricted by the absence electrical controllability short lifetime low exciton funneling efficiency at room temperature, which...

A quantitative single-molecule tip-enhanced Raman spectroscopy (TERS) study at room temperature remained a challenge due to the rapid structural dynamics of molecules exposed air. Here, we demonstrate hyperspectral TERS imaging single or few brilliant cresyl blue (BCB) temperature, along with spectral analyses. Robust chemical is enabled by freeze-frame approach using thin Al2O3 capping layer, which suppresses diffusions and inhibits reactions contamination in For resolved spatially image,...

Controlling electron density in two-dimensional semiconductors is crucial for both comprehensive understanding of fundamental material properties and their technological applications. However, conventional electrostatic doping methods exhibit limitations, particularly addressing electric field–induced drift subsequent diffusion electrons, which restrict nanoscale doping. Here, we present a tip-induced nanospectroscopic pulse modulator to dynamically control density, thereby facilitating...

Strain engineering of perovskite quantum dots (pQDs) enables widely tunable photonic device applications. However, manipulation at the single-emitter level has never been attempted. Here, we present a tip-induced control approach combined with tip-enhanced photoluminescence (TEPL) spectroscopy to engineer strain, bandgap, and emission yield single pQD. Single CsPbBrxI3–x pQDs are clearly resolved through hyperspectral TEPL imaging ∼10 nm spatial resolution. The plasmonic tip then directly...

Optical computing with optical transistors has emerged as a possible solution to the exponentially growing computational workloads, yet an on-chip nano-optical modulation remains challenge due intrinsically noninteracting nature of photons in addition diffraction limit. Here, we present all-optical approach toward nano-excitonic using atomically thin WSe2/Mo0.5W0.5Se2 heterobilayer inside plasmonic tip-based nanocavity. Through wavefront shaping, selectively modulate tip-enhanced...

Gap plasmon (GP) resonance in static surface-enhanced Raman spectroscopy (SERS) structures is generally too narrow and not tunable. Here, we present an adaptive gap-tunable SERS device to selectively enhance modulate different vibrational modes via active flexible Au nanogaps, with optical control. The tunability of GP up ∼1200 cm–1 by engineering gap width, facilitated mechanical bending a polyethylene terephthalate substrate. We confirm that the tuned enhances spectral regions molecules....

High-speed electrical control of nano-optoelectronic properties in two-dimensional semiconductors is a building block for the development excitonic devices, allowing seamless integration nano-electronics and -photonics. Here, we demonstrate high-speed modulation nanoscale exciton behaviors MoS

Emerging light–matter interactions in metal–semiconductor hybrid platforms have attracted considerable attention due to their potential applications optoelectronic devices. Here, we demonstrate plasmon-induced near-field manipulation of trionic responses a MoSe2 monolayer using tip-enhanced cavity-spectroscopy (TECS). The surface plasmon–polariton mode on the Au nanowire can locally manipulate exciton (X0) and trion (X-) populations MoSe2. Furthermore, reveal that charges significantly...

The dynamic nanomechanical strain-engineering of naturally formed wrinkles in a WSe2 monolayer is demonstrated by Kyoung-Duck Park and co-workers article number 2008234, with real-time investigation nanospectroscopic properties using hyperspectral adaptive tip-enhanced PL (a-TEPL) spectroscopy <15 nm spatial resolution. This novel approach allows the exciton dynamics emission 2D semiconductors to be tuned at nanoscale reversible manner.

Atomically Thin Semiconductors In article number 2102893, Junsuk Rho, Kyoung-Duck Park, and co-workers develop a triple-sharp-tips nano-antenna to facilitate radiative emissions of the localized states in 2D semiconductors. The exciton is deterministically induced probed at room temperature through this novel concept tip-enhanced cavity-spectroscopy. This new approach provides practical way control single-photon generation temperature, which centerpiece quantum optical communications.

Emerging photo-induced excitonic processes in transition metal dichalcogenide (TMD) heterobilayers, e.g., coupling, dephasing, and energy transfer of intra- inter-layer excitons, allow new opportunities for ultrathin photonic devices. Yet, with the associated large degree spatial heterogeneity, understanding controlling their complex competing interactions at nanoscale remains a challenge. Here, we present an all-round dynamic control WSe$_2$/Mo$_{0.5}$W$_{0.5}$Se$_2$ heterobilayer using...

The pencil-shaped micropipette is a potentially promising tool for the three-dimensional micro/nanoscale printing based on its capability to deliver low volumes of nanomaterial solution desired spot.

Abstract The generation of high-purity localized trions, dynamic exciton–trion interconversion, and their spatial modulation in 2D semiconductors are building blocks for the realization trion-based optoelectronic devices. Here, we present a method alloptical control exciton-to-trion conversion process its distributions MoS 2 monolayer. We induce nanoscale strain gradient crystal transferred on metal–insulator–metal (MIM) waveguide exploit propagating surface plasmon polaritons (SPPs) to...

Abstract Surface-enhanced Raman spectroscopy (SERS) enables sensitive observations of the chemical properties various materials through highly localized optical field and gap plasmon (GP) resonance attributed to metal nanogap. However, GP excited by static gap-plasmonic structures is too narrow generally not tunable. Thus, tunable or broad-spectral SERS platforms have been little studied. Here, we present an adaptive gap-tunable device selectively enhance modulate different vibrational modes...