High-sensitivity, high-speed, broadband mid-infrared photodetector enabled by a van der Waals heterostructure with a vertical transport channel.

The realization of room-temperature-operated, high-performance, miniaturized, low-power-consumption and Complementary Metal-Oxide-Semiconductor (CMOS)-compatible mid-infrared photodetectors is highly desirable for next-generation optoelectronic applications, but has thus far remained an outstanding challenge using conventional materials. Two-dimensional (2D) heterostructures provide an alternative path toward this goal, yet despite continued efforts, their performance has not matched that of low-temperature HgCdTe photodetectors. Here, we push the detectivity and response speed of a 2D heterostructure-based mid-infrared photodetector to be comparable to, and even superior to, commercial cooled HgCdTe photodetectors by utilizing a vertical transport channel (graphene/black phosphorus/molybdenum disulfide/graphene).

Room-Temperature, Strong Emission of Momentum-Forbidden Interlayer Excitons in Nanocavity-Coupled Twisted van der Waals Heterostructures.

The emission efficiency of interlayer excitons (IEs) in twisted 2D heterostructures has long suffered from momentum mismatch, limiting their applications in ultracompact excitonic devices. Here, we report strong room-temperature emission of momentum-forbidden IE in 30°-twisted MoS/WS heterobilayers. Utilizing a plasmonic nanocavity, the Purcell effect boosts the IE emission intensity in the cavity by over 2 orders of magnitude.

Fast and broadband spatial-photoresistance modulation in graphene-silicon heterojunctions.

Different types of devices with modulable resistance are attractive for the significant potential applications such as sensors, information storage, computation, etc. Although extensive research has been reported on resistance effects, there is still a need for exploring new mechanisms that offer advantages of low power consumption, high sensitivity, and long-term stability. Here, we report a graphene-Si based spatial-dependence photo-rheostat (SDPR), which enables bipolar resistance modulation in the range of 5 mm with a resistance sensitivity exceeding 1,000 Ω/mm at operating wavelengths from visible to near infrared band (1,550 nm).

Van der Waals integrated single-junction light-emitting diodes exceeding 10% quantum efficiency at room temperature.

The construction of miniaturized light-emitting diodes (LEDs) with high external quantum efficiency (EQE) at room temperature remains a challenge for on-chip optoelectronics. Here, we demonstrate microsized LEDs fabricated by a dry-transfer van der Waals (vdW) integration method using typical layered Ruddlesden-Popper perovskites (RPPs). A single-crystalline layered RPP nanoflake is used as the active layer and sandwiched between two few-layer graphene contacts, forming van der Waals LEDs (vdWLEDs).

Room-temperature efficient and tunable interlayer exciton emissions in WS/WSe heterobilayers at high generation rates.

Transition metal dichalcogenide (TMDC) heterobilayers (HBs) have been intensively investigated lately because they offer novel platforms for the exploration of interlayer excitons (IXs). However, the potentials of IXs in TMDC HBs have not been fully studied as efficient and tunable emitters for both photoluminescence (PL) and electroluminescence (EL) at room temperature (RT). Also, the efficiencies of the PL and EL of IXs have not been carefully quantified.

Tailoring Polaron Dimensions in Lead-Tin Hybrid Perovskites.

Charge carriers in the soft and polar perovskite lattice form so-called polaron quasiparticles, charge carriers dressed with a lattice deformation. The spatial extent of a polaron is governed by the material's electron-phonon interaction strength, which determines charge carrier effective mass, mobility, and the so-called Mott polaron density, that is, the maximum stable density of charge carriers that a perovskite can support. Despite its significance, controlling polaron dimensions has been challenging.

Hyperbolic-to-hyperbolic transition at exceptional Reststrahlen point in rare-earth oxyorthosilicates.

Anisotropic optical crystals can exhibit a hyperbolic response within the Reststrahlen band (RB) and support directional polaritonic propagations when interacting with light. Most of the reported low-symmetry optical crystals showcase the evolution from hyperbolic to elliptic dispersion topologies, largely owing to their adjacent RBs being either overlapped or separated. Here, we report an exceptional Reststrahlen point (ERP) in rare-earth oxyorthosilicate YSiO, at which two neighboring RBs almost kiss each other.

Composition Modulation-Mediated Band Alignment Engineering from Type I to Type III in 2D vdW Heterostructures.

Band alignment engineering is crucial for facilitating charge separation and transfer in optoelectronic devices, which ultimately dictates the behavior of Van der Waals heterostructures (vdWH)-based photodetectors and light emitting diode (LEDs). However, the impact of the band offset in vdWHs on important figures of merit in optoelectronic devices has not yet been systematically analyzed. Herein, the regulation of band alignment in WSe/BiTe Se vdWHs (0 ≤ x ≤ 3) is demonstrated through the implementation of chemical vapor deposition (CVD).

High efficiency graphene-silicon hybrid-integrated thermal and electro-optical modulators.

Graphene modulators are considered a potential solution for achieving high-efficiency light modulation, and graphene-silicon hybrid-integrated modulators are particularly favorable due to their CMOS compatibility and low cost. The exploitation of graphene modulator latent capabilities remains an ongoing endeavour to improve the modulation and energy efficiency. Here, high-efficiency graphene-silicon hybrid-integrated thermal and electro-optical modulators are realized using gold-assisted transfer.

Validated enhancement and temperature modulated absorbance of a WS monolayer based on a planar structure.

Transition-metal dichalcogenides (TMDCs), as emerging optoelectronic materials, necessitate the establishment of an experimentally viable system to study their interaction with light. In this study, we propose and analyze a WS/PMMA/Ag planar Fabry-Perot (F-P) cavity, enabling the direct experimental measurement of WS absorbance. By optimizing the structure, the absorbance of A exciton of WS up to 0.

Rational design of a near-infrared fluorescent probe for monitoring butyrylcholinesterase activity and its application in development of inhibitors.

Butyrylcholinesterase (BChE) is widely expressed in multiple tissues and has a vital role in several key human disorders, such as Alzheimer's disease and tumorigenesis. However, the role of BChE in human disorders has not been investigated. Thus, to quantitatively detect and visualize dynamical variations in BChE activity is essential for exploring the biological roles of BChE in the progression of a number of human disorders.

Phase-engineered synthesis of atomically thin te single crystals with high on-state currents.

Multiple structural phases of tellurium (Te) have opened up various opportunities for the development of two-dimensional (2D) electronics and optoelectronics. However, the phase-engineered synthesis of 2D Te at the atomic level remains a substantial challenge. Herein, we design an atomic cluster density and interface-guided multiple control strategy for phase- and thickness-controlled synthesis of α-Te nanosheets and β-Te nanoribbons (from monolayer to tens of μm) on WS substrates.

Study of IL-17 and Intercellular Adhesion Molecule-1 in Conjunctivochalasis Using Correlation Analysis.

Purpose: The aim of this study was to observe the expression of interleukin (IL)-17 and intercellular adhesion molecule (ICAM)-1 in conjunctivochalasis (CCH) and to analyze the correlations between cytokines and the severity of CCH.

Methods: Serum samples were collected from 22 patients with CCH and 18 normal controls (NCs). The Ocular Surface Disease Index, tear film break-up time, Schirmer I test, and corneal fluorescein staining were used to evaluate the ocular surface signs and symptoms.

Exploring and Engineering 2D Transition Metal Dichalcogenides toward Ultimate SERS Performance.

Surface-enhanced Raman spectroscopy (SERS) is an ultrasensitive surface analysis technique that is widely used in chemical sensing, bioanalysis, and environmental monitoring. The design of the SERS substrates is crucial for obtaining high-quality SERS signals. Recently, 2D transition metal dichalcogenides (2D TMDs) have emerged as high-performance SERS substrates due to their superior stability, ease of fabrication, biocompatibility, controllable doping, and tunable bandgaps and excitons.

Microwave ablation enhances the systemic immune response in patients with lung cancer.

Microwave ablation (MWA) is a key alternative therapy to conventional surgery for the treatment of lung cancer. In addition to eliminating local tumors, MWA may promote antitumor immunological responses, such as abscopal effects in distant lesions. However, the intensity of MWA is limited and the underlying mechanisms are not well-defined.

Exploration of the mechanism of Qi-Xian decoction in asthmatic mice using metabolomics combined with network pharmacology.

Qi-Xian Decoction (QXD), a traditional Chinese medicine (TCM) formula consisting of eight herbs, has been clinically used to treat asthma. However, the underlying mechanisms have not been completely elucidated. This study aimed to combine metabolomics and network pharmacology to reveal the mechanism of action of QXD in asthma treatment.

Interfacial Effect on the Transient Dielectric Function and Charge Transfer in a Monolayer WS/Si Heterojunction.

Monolayer tungsten disulfide (WS) is a highly promising material for silicon photonics. Thus, the WS/Si interface plays a very important role due to the interfacial complex effects and abundant states. Among them, the effect of charge transfer on exciton dynamics and the optoelectronic property is determined by the dielectric function, which is very crucial for the performance of optoelectronic devices.

Volume-Confined Fabrication of Large-Scale Single-Crystalline Molecular Ferroelectric Thin Films and Their Applications in 2D Materials.

With outstanding advantages of chemical synthesis, structural diversity, and mechanical flexibility, molecular ferroelectrics have attracted increasing attention, demonstrating themselves as promising candidates for next-generation wearable electronics and flexible devices in the film form. However, it remains a challenge to grow high-quality thin films of molecular ferroelectrics. To address the above issue, a volume-confined method is utilized to achieve ultrasmooth single-crystal molecular ferroelectric thin films at the sub-centimeter scale, with the thickness controlled in the range of 100-1000 nm.

High-Responsivity and Broadband MoS Photodetector Using Interfacial Engineering.

Combining MoS with mature silicon technology is an effective method for preparing high-performance photodetectors. However, the previously studied MoS/silicon-based heterojunction photodetectors cannot simultaneously demonstrate high responsivity, a fast response time, and broad spectral detection. We constructed a broad spectral n-type MoS/p-type silicon-based heterojunction photodetector.

Silver nanoparticle-induced enhancement of light extraction in two-dimensional light-emitting diodes.

Monolayer transition metal dichalcogenides (TMDCs) with direct bandgaps are considered promising candidates for building light-emitting diodes (LEDs). One crucial indicator of their performance is the brightness of electroluminescence (EL). In this study, we fabricate WS-based LEDs that make full use of the assistance of effective transient-mode charge injection.

Wogonin alleviates BaP-induced DNA damage and oxidative stress in human airway epithelial cells by dual inhibiting CYP1A1 activity and expression.

Benzo[a]pyrene (BaP) is a common air pollutant that has been reported to cause oxidative stress and carcinogenesis. Wogonin, a flavonoid compound extracted from the roots of Scutellaria baicalensis, has been found to possess a variety of pharmacological activities, including anti-inflammatory and anti-cancer effects. The purpose of this study was to examine the ability of wogonin to alleviate the cytotoxicity induced by BaP in human airway epithelial cells and explore the corresponding mechanism.

Alloy Engineering Allows On-Demand Design of Ultrasensitive Monolayer Semiconductor SERS Substrates.

The chemical mechanism (CM) of surface-enhanced Raman scattering (SERS) has been recognized as a decent approach to mildly amplify Raman scattering. However, the insufficient charge transfer (CT) between the SERS substrate and molecules always results in unsatisfying Raman enhancement, exerting a substantial restriction for CM-based SERS. In principle, CT is dominated by the coupling between the energy levels of a semiconductor-molecule system and the laser wavelength, whereas precise tuning of the energy levels is intrinsically difficult.