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This paper proposed a point matching algorithm based on Mahalanobis distance and analyzed its performance. Due to the limitation of Mahalanobis distance and weighted graph transformation, it embedded the similarity evaluated by mahalanobis distance into WGTM algorithm. It proposed a novel and robust image matching strategy, the algorithm based on weighted graph transformation using Mahalanobis distance. It built the weight matrix by using the median of mahalanobis distance and angular distances between edges that connect a feature point to its K-nearest neighbors in the graph. It updated the graph according to the weight ever-updating. It obtained then precise results of the point pairs matching through iteratively eliminating the outliers. Experimental results on synthetic data and real-world data have demonstrated that the proposed algorithm is effective and robust. [ABSTRACT FROM AUTHOR]

Abstract: We report the experimental results on characteristics of co-existence of third-order and transient thermally induced optical nonlinearities using a nanosecond pulse laser and CS2 solutions of nigrosine. Results show that thermally induced optical nonlinearity is very sensitive to linear absorption, beam waist size and pulsewidth. Numerical simulations obtained by solving simultaneously acoustic and electromagnetic wave equations, agrees basically with experimental results. Meanwhile, the transition of optical nonlinearity from self-focusing pattern to self-defocusing pattern was observed when the contribution from thermally induced optical nonlinearity exceeds that from third-order optical nonlinearity. [Copyright &y& Elsevier]

Many novel transport phenomena are observed in graphene nanochannels with ultrahigh surface flatness and nano‐ or sub‐nanoscale constraints. Two critical physical parameters, surface slip length, and surface charge, play a vital role in the channel transport process. However, effectively controlling these parameters under such tight constraints remains a significant challenge. Here, it is developed a novel method that combines oxygen ion etching and layer‐by‐layer assembly of 2D material, to prepare graphene nanochannels. During the assembly process, defects are introduced into the graphene surface via oxygen ion etching. A significantly higher conductivity is observed for the pristine graphene channels compared to those with defects on both the upper and lower surfaces. Consistent with this observation, the conductivity of graphene channels with defects on only one surface falls between the two aforementioned values. Combined with theoretical analysis, the conductivity difference is attributed to the surface slip inhibition due to the introduced defects, and the change of surface charge, both caused by oxygen ion etching. By introducing defects, a new method is uncovered for fine‐tuning ion transport in graphene nanochannels. [ABSTRACT FROM AUTHOR]

A combination of different 2D layered materials by van der Waals (vdW) stacking or lateral splicing provides the basic building blocks for dynamic behavior researches of interlayer carriers. Anisotropic materials, recently, have further attracted attentions in this field because of their supply of freedoms for regulating the performance of electro‐optical devices, whereas detailed characteristics and mechanisms of interlayer carrier transportation in these materials need remain to be revealed. Here, by using the photoassisted field effect and scanning photocurrent imaging measurements, it is demonstrated that the photoinduced interlayer carrier transportation in cross‐stacked black phosphorus (BP) vdW junctions is strongly dependent on the crystal orientation and stacking morphology. Type‐I and II band alignments are respectively predicted in the BP junctions with parallel and vertical crystal orientation stacking. The interlayer carrier transportation with both vertical and lateral modes is observed within only one sample. Combined first principle calculation with band theory analyses, the small band offset for holes and tunneling effect play key roles during the interlayer transportation. These results highlight the importance of crystal orientation of materials in vdW junctions and provide insights, both experimentally and theoretically, into engineering and design of orientation‐based nanodevices. The anisotropy of black phosphorus in its van der Waals structure is demonstrated to influence the photoinduced interlayer carrier transportation greatly by scanning photocurrent imaging measurements and theoretical analysis. The small band offset for holes and tunneling effect play key roles, which indicates the formation of Type‐I (II) band alignments in the black phosphorus junctions with parallel (vertical) crystal orientation stacking. [ABSTRACT FROM AUTHOR]

2D layered materials have sparked great interest from the perspective of basic physics and applied science in the past few years. Extraordinarily, many novel stacked structures that bring versatile properties and applications can be artificially assembled, as exemplified by vertical van der Waals (vdW) heterostructures, twisted multilayer 2D materials, hybrid dimensional structures, etc. Compared with the ordinary synthesis process, the stacking technique is a powerful strategy to achieve high‐quality and freely controlled 2D material stacked structures with atomic accuracy. This review highlights the most advanced stacking techniques involving the preparation, transfer, and stacking of high‐quality single crystal 2D materials. Apart from the 2D–2D stacked structures, 2D–0D, 2D–1D, and 2D–3D structures offer a prospective platform for the increasing application of 2D materials. The assembly strategy and physical properties of these stacked structures strongly depend on the factors in the stacking process, including the surface quality, angle control, and sample size. In addition, comparative analysis tables on the techniques involved are also available. The summary of these strategies and techniques will hopefully provide a valuable reference for relevant work. [ABSTRACT FROM AUTHOR]

The substrate effect is an important issue in the properties of two-dimensional transition metal dichalcogenides (2D TMDs). Quantitatively determining the dependence of the photoluminescence (PL) emission properties and the excitonic behavior of single-layer 2D materials in a specific dielectric environment would provide helpful guidance for the rational design of substrates for high performance 2D TMD PL emission devices. Here, using a WSe2 monolayer on different substrates as a model system, it is demonstrated that the PL emission intensities can drastically change depending on the substrate effect. From the analysis of the excitonic behavior, the results reveal that the spectral weight between the neutral and charged excitons in the PL spectra is significantly modified by the substrate types, and the weight factor is dependent on the laser excitation density. The charged exciton binding energy is obviously negatively related to the substrate dielectric constant. Furthermore, the change trends of the binding energy of the monolayer WSe2 on different substrates are basically the same for the increase of the excitation density. These results suggest that the choice of the substrate plays a significant role in the modulation of the PL properties and exciton states of atomically thin WSe2; hence, substrate engineering should be carefully considered in the design of future 2D devices. [ABSTRACT FROM AUTHOR]

As two important members of two-dimensional (2D) transition metal dichalcogenides, ReS2 and ReSe2 have gained interest for optoelectronic and photonic applications. The key to the application of the 2D materials to the optoelectronic devices is to understand the interaction between light and matter. Here, we report that the chemical vapor deposition-grown few-layer ReS2 and ReSe2 display saturable absorption under 400 nm pulse excitation, measured through intensity dependent transmission and confirmed by ΔT/T spectroscopy. ΔT/T spectroscopy substantiates the coexistence of saturable absorption and excited state absorption at 800 nm for both ReS2 and ReSe2. Two time constants are extracted from time-resolved spectroscopy; the short time constant of 10–20 ps is associated with the relaxation of hot carriers and exciton formation, and the long time constant of 70–100 ps is assigned to exciton lifetime. The polarization dependence of ΔT/T reveals that the initial distribution of photoexcited carriers centered at excitation state is anisotropic, and this initial anisotropy loses rapidly with carrier relaxation. The nonequilibrium carriers scattered far away from excitation state are fully isotropic in the entire relaxation process. These findings provide fundamental information for using the two materials in ultrafast optoelectronic and photonic devices. [ABSTRACT FROM AUTHOR]

We carried out a detailed investigation on a compact in-line multimode single-mode multimode (MSM) fiber structure. Both theoretical modal and experimental setup were established to demonstrate the transmission characteristics and the corresponding responses of the applied strain and temperature. The proposed structure simply involves a section of the single-mode fiber (SMF) spliced to two sections of multimode fiber (MMF) and lead-in and lead-out SMFs. The excited environment-sensitive cladding modes together with the fundamental mode in the central SMF form a typical Mach–Zehnder interferometer (MZI). We analyzed the transmission characteristics of the different length of the middle SMF and the MMF in detail. In the experiment, we obtained the extinction ratio of the MSM fiber structure based MZI comb spectrum which was up to 20 dB, and sensitivities of 0.7096 pm/με (0–2000 με) and 44.12 pm/°C (10–70 °C), which proved the potential sensing applications of the proposed fiber structure. [ABSTRACT FROM AUTHOR]

Knoxia roxburghii (Spreng.) M. A. Rau (KR) is a plant clinically used in traditional Chinese medicine (TCM) for the treatment of cancer. The study objectives were to examine the effects of KR extracts, petroleum ether (PET), ethyl acetate (EtoAc), butanol (n-BuOH), and H2O-soluble fractions (HSF) of the 75% EtOH extraction on A549 (non-small cell lung cancer), HepG2 (liver cancer), HeLa (cervical cancer), MCF-7 (breast cancer), and L02 (normal hepatocyte) cells. It was found that HSF exhibited the strongest cytotoxic activity against MCF-7 cells, and was accompanied by reduced mitochondrial transmembrane potential, increased levels of intra-cellular reactive oxygen species (ROS) and activated caspases, and upregulated pro-apoptotic and downregulated anti-apoptotic proteins. LC-MS analysis further showed that HSF primarily consisted of calycosin, aloe emodin, rein, maackiain, asperuloside, orientin, vicenin-2, and kaempferide, which have been mostly reported for anti-tumor activity in previous studies. In summary, the current study illustrated the effect, mechanism, and the potential major active components of KR against breast cancer. [ABSTRACT FROM AUTHOR]

The pressure–temperature (P‐T) path of blueschist is usually applied to understanding the evolution of the subducted oceanic crust. Garnet plays a key role in calculating the metamorphic conditions, but sometimes it is absent in the blueschists. Nevertheless, the high‐P experimental simulation may serve as a useful tool to constrain the P‐T conditions. In the middle of the Longmu Co‐Shuanghu Suture, North Tibet, blueschist blocks embedded in the marble were discovered, where garnet is abundant in the core but absent in the marble‐contacting margin. These two kinds of blueschist contain similar mineral assemblage (glaucophane, epidote, and phengite) and show comparable basaltic character. Pseudosection modelling was applied to the garnet‐bearing blueschist that calculated the peak metamorphic condition of ca. 1.9 GPa and 530°C. As for the garnet‐absent blueschist, experiments (1.2–2.3 GPa and 500–800°C) were performed on the designed mixture of 93 wt% basalt and 7 wt% calcite. The results show that the total Fe content in the glaucophane and barroisite is positively correlated with the pressure but not with temperature, which could be regarded as a geobarometer. Accordingly, the peak condition was constrained at 2.3 GPa and 500–600°C. Therefore, the equivalent metamorphic conditions of the blueschists indicate that the Palaeo‐Tethys oceanic crust subducted into at least 70 km. Furthermore, both the experiments and the T‐X (CaCO3) pseudosection, constructed based on basaltic lithology, support that the absence of garnet in the blueschist is predominantly caused by the mixing of calcite. In summary, this study provides a valid attempt in exploring metamorphic conditions by experiment simulation, and evaluates the profound influence of the interaction between the basaltic crust and overlying carbonate‐bearing sediments in the subduction zone. [ABSTRACT FROM AUTHOR]

Abstract: The nonlinear absorption properties of tetraphenylporphyrins (TPP) in different solvents and excitation intensities are investigated with nanosecond pulses by the Z-scan technique. The nonlinear absorption behaviour observed presents a distinct difference between in solvent mixtures and in pure solvents. A crossover from reverse saturable absorption (RSA) to saturable absorption (SA) and then again to RSA is observed with the increases of excitation intensity in chloroform and pyridine mixed solvents. However, porphyrin molecules in pure solvents show good RSA behaviour under the studied intensity range, no saturation absorption is observed with nanosecond excitation. Excited state absorption parameters and two-photon absorption coefficients are obtained by theoretical fit using rate equations for population densities in a seven-level energy scheme. [Copyright &y& Elsevier]

Abstract: We apply a new method consisting of a coordinate transformation and a coordinate mapping technique, to simulate numerically Z-scan measurements of a nonlinear medium. A comparison of numerical results obtained by this new method with those by conventional numerical method is made. Results show that the new scheme yields a large, orders-of-magnitude range improvement in computational speed and accuracy for the analyses of closed-aperture and open-aperture Z-scan measurements, compared with conventional numerical methods. [Copyright &y& Elsevier]

We study the Goos–Hänchen (GH) effect in mechanically exfoliated anisotropic two-dimensional (2D) black phosphorus and rhenium disulfide by using a beam displacement amplification technique. We observed anisotropic GH shifts along different crystal orientations of two 2D materials, and they exhibit different anisotropy characteristics. It is because the GH shift is mainly affected by the phase shift of light in the 2D materials, which is related to the real part of the refractive index, while the absorption effect related to the imaginary part of the refractive index has negligible influence on the GH shift. The GH shift can be applied to explore the anisotropy of the real part of the refractive index of a 2D material. Our results provide an important way to reveal the anisotropy mechanism of 2D materials. [ABSTRACT FROM AUTHOR]

Thermal management plays an important role in miniaturized and integrated nanoelectronic devices, where finding ways to enable efficient heat‐dissipation can be critical. 2D materials, especially graphene and hexagonal boron nitride (h‐BN), are generally regarded as ideal materials for thermal management due to their high inherent thermal conductivity. In this paper, a new method is reported, which can be used to characterize thermal transport in 2D materials. The separation of pumping from detection can obtain the temperature at different distances from the heat source, which makes it possible to study the heat distribution of 2D materials. Using this method, the thermal conductivity of graphene and molybdenum disulfide is measured, and the thermal diffusion for different shapes of graphene is explored. It is found that thermal transport in graphene changes when the surrounding environment changes. In addition, thermal transport is restricted at the boundary. These processes are accurately simulated using the finite element method, and the simulated results agree well with the experiment. Furthermore, by depositing a layer of h‐BN on graphene, the heat‐dissipation characteristics of graphene become tunable. This study introduces and describes a new method to investigate and optimize thermal management in 2D materials. [ABSTRACT FROM AUTHOR]

The identification of a microcontinent in Bangong–Nujiang suture zone (BNSZ) is important to understanding the tectonic evolution of Bangong–Nujiang Tethys Ocean (BNTO). Subduction‐related ophiolite is one of the keys to discriminate a microcontinent in suture zones, which can be generated during the oceanic subduction beneath the microcontinent. Generally, ophiolites in the adjacent area of a microcontinent would show characteristics of a volcanic arc, while ophiolites in adjacent area of an ocean show characteristics of a fore‐arc. North Pengco ophiolites (NPOs) and South Pengco ophiolites (SPOs) were collected in the central section of BNSZ, and dated at 115.0–111.5 Ma by SHRIMP II. According to their trace element characteristics, NPOs were determined to have formed at a setting of subduction‐related volcanic arc and affected by slab‐derived fluids or melts. The diagram based on the Ce versus Ce/Y shows that NPOs originated from the partial melting of spinel peridotites. On the other hand, SPOs were generated from the partial melting of ultra‐depleted mantle at a setting of subduction‐related fore‐arc on the basis of extraordinarily low REEs summation and HFSEs (e.g., Zr, Ti, Nb and Ta), relatively high concentrations of compatible elements (e.g., Cr, Ni), large ratios of CaO/TiO2 (37.67–437.50) and Al2O3/TiO2 (20.78–424.50), which were also affected by slab‐derived fluids. Based on the relative location of NPOs and SPOs, it reasonably proposed that a northward subduction of a minor oceanic basin had occurred at the Early Cretaceous, trigged by the Dongkaco microcontinent (DMC). In reverse, these ophiolites provide evidence for the existence of DMC in BNTO. Combining with other subduction‐related ophiolites developed in BNSZ, BNTO might have comprised of several minor oceanic basins separated by some blocks like DMC in the central and west sections, rather than a unified ocean basin. [ABSTRACT FROM AUTHOR]

The bandgap, electrical, and optical properties of PtSe2 depend dramatically on the vertical stacking and fabrication method. Here, we study the nonlinear absorption properties of the PtSe2 films composed of both semiconducting and semimetallic phases in a single film. These PtSe2 films exhibit remarkable thickness-dependent saturable absorption for femtosecond pulses at 400 nm and 800 nm. The saturation intensities decrease with the increase in the film thickness due to the accompanied increase in the semimetallic component and are much smaller than the reported values of PtSe2 synthesized by thermally assisted conversion. The saturable absorption characteristics are confirmed by time-resolved spectroscopies. The nonlinear refractive indexes of these PtSe2 films should be smaller than 1 × 10–12 cm2/W. Our results imply that the optical nonlinearities of PtSe2 could be flexibly tuned by the synthesis method and thickness. [ABSTRACT FROM AUTHOR]

We simulated hydraulic fracturing in different lithologic rocks in the horizontal drilling by using the true physical model experiment and large rock specimens, carried out the real-time dynamic monitoring with adding tracer and then did post-fracturing cutting and so on. Based on this monitoring results, we compared and assessed the factors affecting expansion in shale, shell limestone, and tight sandstone and the fracture expansion in these rocks. In shale, the reformed reservoir volume is the highest, fracture network is formed in the process of fracturing. In tight sandstone, the fracture surface boundaries are curved, and the fracture surface area accounts for 25–50% of the entire specimen. In shell limestone, the complexity of the fracture morphology is between shale and tight sandstone, but no fracture network is developed. Brittleness controls the fracture surface area. In highly brittle rocks, the fracture surface area is high. Fracture toughness mainly affects the initiation and propagation of cracks. A fracture network is formed only if bedding planes are present and are more weaker than their corresponding matrix. The horizontal in situ deviatoric stress affects the crack propagation direction, and different lithologies have different horizontal in situ deviatoric stress thresholds. Low fluid injection rate facilitates the formation of complex cracks, whereas high fluid injection rate favors the development of fractures. Fluid injection weakly controls the complexity of hydraulic fracturing in low-brittleness rocks, whereas low-viscosity fracturing fluids favor the formation of complex cracks owing to easy enter microcracks and micro-pore. Displacement has a greater impact on high brittle rocks than low brittle rocks. [ABSTRACT FROM AUTHOR]

A sensitive and selective optical biosensor based on reduced graphene oxide (RGO), which uses the polarization-dependent absorption effect of graphene under total internal reflection, is reported for determination of rabbit IgG. RGO sheets with the thickness of about 8.1 nm are fabricated by high temperature reduction and used as a sensing film, because of its strong polarization dependent absorption. This RGO-based optical sensor shows a satisfactory response to rabbit IgG with a minimum concentration of 0.0625 μg/ml. As a contrast, commercial SPR apparatus is used to investigate rabbit IgG with a minimum concentration of 0.3125 μg/ml. Moreover, with antigen–antibody binding, this sensor can also achieve label-free and real-time detection. Taking into account these factors, the RGO-based optical sensor may be a potential candidate for biosensing. [ABSTRACT FROM AUTHOR]

We report new zircon U–Pb ages and Hf isotope compositions, and whole-rock major and trace element and Sr–Nd isotope data for the Meiriqiecuo Formation (MF) bimodal volcanic rocks collected from the Duolong Cu mining district (DCMD) in the western Qiangtang terrane (QT), western Tibet. These data provide important constraints on the petrogenetic evolution and geodynamic setting of Early Cretaceous magmatism in the DCMD. The MF bimodal volcanic rocks are mainly basaltic andesite and andesite, with subordinate rhyolite. Four mafic samples yielded zircon U–Pb ages of ca. 108.2–113.0 Ma, and one silicic sample has an age of 109.3 ± 2.2 Ma, indicating that the mafic and silicic eruptions were contemporaneous. The MF bimodal volcanic rocks belong to the medium-K calc-alkaline to shoshonite series. The rocks show arc-type affinities characterized by significant enrichment in light rare earth (La N /Yb N = 7.74–12.60) and large-ion lithophile elements (Rb, Cs, K, and Pb), but depletions in the high-field-strength elements (Nb, Ta, and Ti), which geochemically resemble Andean arc basalts. Therefore, the MF bimodal volcanic rocks were likely emplaced at an Andean-type active continental margin and represent an Early Cretaceous magmatic arc that was located at the western QT margin. Moreover, the mafic volcanic rocks have high initial Sr isotopic ratios (0.705269–0.705413) and negative ε Nd (t) values of −1.5 to −0.6 compared with the silicic volcanic rocks (( 87 Sr/ 86 Sr) i = 0.704770–0.704903; ε Nd (t) = +1.2 to +1.3). Zircons from silicic samples have significantly higher ε Hf (t) values (+11.6 to +15.5) and predominantly lower Paleoproterozoic Hf crustal model ages ( T DMC = 180–428 Ma) than the mafic samples, which have variable ε Hf (t) values of +3.4 to +13.0 and T DMC ages of 346–952 Ma. These results indicate that the mafic and silicic end-members of the MF bimodal suite were generated from mantle and crustal sources, respectively. The basaltic andesite and andesite may have been derived from mantle enriched by the metasomatism of subducted fluids, whereas the rhyolite could have been derived by partial melting of mafic juvenile crust that originated from an older and more depleted mantle. In light of the geochemical characteristics and field relationships, we propose that breakoff of the Bangong–Nujiang oceanic lithosphere was responsible for the generation and emplacement of the MF bimodal volcanic rocks. The fact that the MF bimodal volcanic arc magmatism was active at ca. 108–113 Ma indicates that it was associated with closure of the Bangong–Nujiang Ocean via an arc-arc “soft” collision during the Early Cretaceous. [ABSTRACT FROM AUTHOR]

Passive daytime radiative cooling (PDRC), a green cooling technology with energy-free consumption, has demonstrated great potential in solving global warming and other problems. Dielectric particles embedded in polymers are considered efficient radiative cooling strategies devoted to solving the problems of the complex preparation process and low cooling efficiency. However, the high ultraviolet ray (UV) absorption or low refractive index of dielectric materials results in their low solar scattering. Herein, we propose a simple and efficient method to prepare a radiative cooling coating consisting of yttrium oxide (Y 2 O 3) and polydimethylsiloxane (PDMS). The PDMS/Y 2 O 3 radiative cooling film was fabricated according to the theoretically optimized particle size, volume fraction, and coating thickness. The result indicated that the randomly distributed Y 2 O 3 nanoparticles were employed in PDMS to enhance the scattering efficiency of sunlight. The solar reflectance and "atmospheric window" emissivity of the PDMS/Y 2 O 3 film was about 94.52% and 93.4%. Outdoor cooling tests exhibited that the PDMS/Y 2 O 3 hybrid film could achieve sub-ambient radiative cooling of 7. 4 °C under solar irradiation of 1132 W/m2. In comparison, commercial white paint was 1. 8 °C higher than ambient temperature. Consequently, the film is promising for large-scale applications in green buildings, cold chain logistics, photovoltaic fields, modern agricultural production, and other fields. • A simple and extensible method was designed to prepare PDMS/ Y 2 O 3 composite film. • Both solar reflectance and IR emittance can be 94.52% and 93.4% of the PDRC film. • Sub-ambient cooling of 7.4 °C could be achieved during the day with the film. • Besides the radiative cooling properties, the film also has that adaptability, stability, and hydrophobicity. [ABSTRACT FROM AUTHOR]

Magmatic flare-ups are well recognized as a fundamental feature of continental arc magmatism, but its driven mechanism still remains unresolved. Exploring this behavior is of significance in unraveling the deep dynamic processes related to plate subduction and crustal growth. In central Tibet, arc magmatism within the South Qiangtang terrane (SQT) caused by the northward subduction of the Bangong-Nujiang Ocean (BNO) is featured by a prominent high-flux event during Jurassic, but its details and corresponding geodynamic background are not determined. This paper reports geochronological and geochemical data of the granodiorites near the Rigen Co area in the middle part of SQT. These rocks were generated at ca. 150 Ma and display typical adakitic characters. Their low MgO (1.41–2.39 wt%), initial 87Sr/86Sr ratios (0.7055–0.7059) and slightly low ε Nd (t) values (−1.9 to −1.2), and high zircon ε Hf (t) (+1.9 to +8.4) and δ18O values (+6.6 to +9.2 ‰) suggest the adakitic granodiorites were derived from partial melting of subducted crust involving 10–20% inputs of overlying sediment. Our sample, together with previous reports delineates a distinct slab-window association (adakite and oceanic island basalt (OIB)-type diabase) along the southmost of SQT, which coincided with the magmatic flare-up at ca. 155 Ma as revealed by the age spectra of magmatic rocks and complementary detrital zircons. Furthermore, a trench-ward migration is recognized for the arc magmatism from ca. 170 Ma to 155 Ma, implying a slab-roll back process. Accordingly, this high-flux event with the slab-window formation is best explained by the trigger of ensuing slab break-off. These results, combined with other geological evidence, contribute new constraints on elucidating the Jurassic geodynamic evolution of the BNO subduction. • The Rigen Co granodiorites were generated by oceanic crust melting at ca. 150 Ma. • Jurassic arc magmatism in the South Qiangtang terrane shows a trench-ward migration. • The Late Jurassic magmatic flare-up was triggered by slab break-off. • A oceanic plateau-continent collision was proposed to explain these processes. [ABSTRACT FROM AUTHOR]

Highlights: [•] The nonlinear optical properties of three graphene hybrid materials are studied. [•] In nanosecond regime, RGO–ZnPc shows better optical limiting properties. [•] In femtosecond regime, GO–ZnPc shows better nonlinear optical properties. [•] The interaction between graphene and ZnPc causes optical nonlinearity enhancement. [ABSTRACT FROM AUTHOR]

• The oxide layer thicknesses of black phosphorus was controlled by the etching time. • The tunneling effect rectification is related to the oxide layer thicknesses of black phosphorus. • Negative differential resistance effect were observed with longer etching times. • The controllable tunneling effect could help in the design novel optoelectronic devices. Due to its low chemical stability, the surface of black phosphorus (Bp) easily oxidizes to form an oxide layer, which can be used to realize effective electronic tunneling devices. Here, we reported a controllable graphene/Bp van der Waals heterostructure tunneling device by controlling the oxidation etching time. We developed a method for fabricating oxide layers with controllable thickness and realized different thickness oxide layers in different regions of the sample. Through comparative experiments, it was found that as the etching time increased, the tunneling effect was gradually enhanced, and a rectification effect was revealed that also tended to increase. The controllable Bp tunneling effect could help in the design of novel optoelectronic devices. [ABSTRACT FROM AUTHOR]

As the most promising candidates for the implementation of in-sensor computing, retinomorphic vision sensors can constitute built-in neural networks and directly implement multiply-and-accumulation operations using responsivities as the weights. However, existing retinomorphic vision sensors mainly use a sustained gate bias to maintain the responsivity due to its volatile nature. Here, we propose an ion-induced localized-field strategy to develop retinomorphic vision sensors with nonvolatile tunable responsivity in both positive and negative regimes and construct a broadband and reconfigurable sensory network with locally stored weights to implement in-sensor convolutional processing in spectral range of 400 to 1800 nanometers. In addition to in-sensor computing, this retinomorphic device can implement in-memory computing benefiting from the nonvolatile tunable conductance, and a complete neuromorphic visual system involving front-end in-sensor computing and back-end in-memory computing architectures has been constructed, executing supervised and unsupervised learning tasks as demonstrations. This work paves the way for the development of high-speed and low-power neuromorphic machine vision for time-critical and data-intensive applications.

The quantum Hall effect, fundamental in modern condensed matter physics, continuously inspires new theories and predicts emergent phases of matter. Here we experimentally demonstrate three types of Chern insulators with synthetic dimensions on a programable 30-qubit-ladder superconducting processor. We directly measure the band structures of the 2D Chern insulator along synthetic dimensions with various configurations of Aubry-André-Harper chains and observe dynamical localisation of edge excitations. With these two signatures of topology, our experiments implement the bulk-edge correspondence in the synthetic 2D Chern insulator. Moreover, we simulate two different bilayer Chern insulators on the ladder-type superconducting processor. With the same and opposite periodically modulated on-site potentials for two coupled chains, we simulate topologically nontrivial edge states with zero Hall conductivity and a Chern insulator with higher Chern numbers, respectively. Our work shows the potential of using superconducting qubits for investigating different intriguing topological phases of quantum matter., (© 2023. Springer Nature Limited.)

Stacked 2D perovskites provide more possibilities for next generation photodetector with more new features. Compared with its excellent optoelectronic properties, the good dielectric performance of metal halide perovskite rarely comes into notice. Here, a bifunctional perovskite based photovoltaic detector capable of two wavelength demultiplexing is demonstrated. In the Black Phosphorus/Perovskite/MoS 2 structured photodetector, the comprehensive utilization of the photosensitive and dielectric properties of 2D perovskite allows the device to work in different modes. The device shows normal continuous photoresponse under 405 nm, while it shows a transient spike response to visible light with longer wavelengths. The linear dynamic range, rise/decay time, and self-powered responsivity under 405 nm can reach 100, 38 µs/50 µs, and 17.7 mA W -1 , respectively. It is demonstrated that the transient spike photocurrent with long wavelength exposure is related to the illumination intensity and can coexist with normal photoresponse. Two waveband-dependent signals can be identified and used to reflect more information simultaneously. This work provides a new strategy for multispectral detection and demultiplexing, which can be used to improve data transfer rates and encrypted communications. This work mode can inspire more multispectral photodetectors with different stacked 2D materials, especially to the optoelectronic application of the wide bandgap, high dielectric photosensitive materials., (© 2023 Wiley-VCH GmbH.)

Simulating response properties of molecules is crucial for interpreting experimental spectroscopies and accelerating materials design. However, it remains a long-standing computational challenge for electronic structure methods on classical computers. While quantum computers hold the promise of solving this problem more efficiently in the long run, existing quantum algorithms requiring deep quantum circuits are infeasible for near-term noisy quantum processors. Herein, we introduce a pragmatic variational quantum response (VQR) algorithm for response properties, which circumvents the need for deep quantum circuits. Using this algorithm, we report the first simulation of linear response properties of molecules including dynamic polarizabilities and absorption spectra on a superconducting quantum processor. Our results indicate that a large class of important dynamical properties, such as Green's functions, are within the reach of near-term quantum hardware using this algorithm in combination with suitable error mitigation techniques.

Tuning the thermal properties of materials is considered to be of crucial significance for improving the performance of electronic devices. Along these lines, the development of van der Waals (vdW) heterostructures becomes an effective solution to affect the thermal transport mechanisms. However, vdW interactions usually block phonon transport, which leads to a reduction in thermal conductivity. In this work, we experimentally demonstrate a large enhancement in the thermal conductivity of a vdW heterostructure composed of few-layer hexagonal boron nitride (h-BN) and reduced graphene oxide (RGO). By controlling the reduction temperature of RGO and changing the thickness of h-BN, the thermal conductivity of the RGO is increased by nearly 18 times, namely, from 91 to 1685 W m -1 K -1 . Photothermal scanning imaging is used to reveal the changes in the heat transfer and temperature distribution of the h-BN/RGO heterostructure. Both photothermal scanning and Raman spectroscopy experiments show that the vdW interaction between h-BN and RGO can greatly increase the thermal conductivity of RGO, which is in contrast to the conventional understanding that vdW interaction reduces thermal conductivity. Our work paves the way for the manipulation of the thermal conductivity of two-dimensional (2D) heterostructures, which could be of great significance for future nanoelectronic circuits.

Background: N6-methyladenosine (m6A) methylation played a key role in tumor growth. However, the relationship between m6A and soft tissue sarcoma (STS) was still unclear. Methods: The characterization and patterns of m6A modification in STS (TCGA-SARC and GSE17674) were analyzed comprehensively through bioinformatics and real-time polymerase chain reaction (RT-PCR). The effects of different m6A modification patterns on prognosis and immune infiltration of STS were further explored. Differentially expressed gene (DEG) analysis was performed. Moreover, an m6Ascore was constructed by principal component analysis (PCA). In addition, two immunotherapy datasets (IMvigor210 and GSE78220) and a sarcoma dataset (GSE17618) were used to evaluate the m6Ascore. Results: Huge differences were found in somatic mutation, CNV, and expression of 25 m6A regulators in STS. Two modification patterns (A and B) in STS were further identified and the m6A cluster A showed a better clinical outcome with a lower immune/stromal score compared with the m6A cluster B ( p < 0.050).In addition to , most STS samples from m6A cluster A showed a high m6Ascore, which was related to mismatch repair and a better prognosis of STS ( p < 0.001). In contrast, the m6A cluster B, characterized by a low m6Ascore, was related to the MYC signaling pathway, which led to a poor prognosis of STS. A high m6Ascore also contributed to a better outcome of PD-1/PD-L1 blockade immunotherapy. Conclusion: The modification patterns of 25 m6A regulators in the STS microenvironment were explored comprehensively. The novel m6Ascore effectively predicted the characteristics of the tumor microenvironment (TME) and outcome in STS and provided novel insights for future immunotherapy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Xiao, Yang, Yan, Liu, Yang, Guo and Cai.)

Recently, palladium diselenide (PdSe 2 ) has emerged as a promising material with potential applications in electronic and optoelectronic devices due to its intriguing electronic and optical properties. The performance of the device is strongly dependent on the charge-carrier dynamics and the related hot phonon behavior. Here, we investigate the photoexcited-carrier dynamics and coherent acoustic phonon (CAP) oscillations in mechanically exfoliated PdSe 2 flakes with a thickness ranging from 10.6 nm to 54 nm using time-resolved non-degenerate pump-probe transient reflection (TR) spectroscopy. The results imply that the CAP frequency is thickness-dependent. Polarization-resolved transient reflection (PRTR) measurements reveal the isotropic charge-carrier relaxation dynamics and the CAP frequency in the 10.6 nm region. In addition, the deformation potential (DP) mechanism dominates the generation of the CAP. Moreover, a sound velocity of 6.78 × 10 3 m s -1 is extracted from the variation of the oscillation period with the flake thickness and the delay time of the acoustic echo. These results provide insight into the ultrafast optical coherent acoustic phonon and optoelectronic properties of PdSe 2 and may open new possibilities for PdSe 2 applications in THz-frequency mechanical resonators.

Background: Osteosarcoma is one of the most common bone tumors among children. Tumor-associated macrophages have been found to interact with tumor cells, secreting a variety of cytokines about tumor growth, metastasis, and prognosis. This study aimed to identify macrophage-associated genes (MAGs) signatures to predict the prognosis of osteosarcoma., Methods: Totally 384 MAGs were collected from GSEA software C7: immunologic signature gene sets. Differential gene expression (DGE) analysis was performed between normal bone samples and osteosarcoma samples in GSE99671. Kaplan-Meier survival analysis was performed to identify prognostic MAGs in TARGET-OS. Decision curve analysis (DCA), nomogram, receiver operating characteristic (ROC), and survival curve analysis were further used to assess our risk model. All genes from TARGET-OS were used for gene set enrichment analysis (GSEA). Immune infiltration of osteosarcoma sample was calculated using CIBERSORT and ESTIMATE packages. The independent test data set GSE21257 from gene expression omnibus (GEO) was used to validate our risk model., Results: 5 MAGs (MAP3K5, PML, WDR1, BAMBI, and GNPDA2) were screened based on protein-protein interaction (PPI), DGE, and survival analysis. A novel macrophage-associated risk model was constructed to predict a risk score based on multivariate Cox regression analysis. The high-risk group showed a worse prognosis of osteosarcoma ( p  < 0.001) while the low-risk group had higher immune and stromal scores. The risk score was identified as an independent prognostic factor for osteosarcoma. MAGs model for diagnosis of osteosarcoma had a better net clinical benefit based on DCA. The nomogram and ROC curve also effectively predicted the prognosis of osteosarcoma. Besides, the validation result was consistent with the result of TARGET-OS., Conclusions: A novel macrophage-associated risk score to differentiate low- and high-risk groups of osteosarcoma was constructed based on integrative bioinformatics analysis. Macrophages might affect the prognosis of osteosarcoma through macrophage differentiation pathways and bring novel sights for the progression and prognosis of osteosarcoma., Competing Interests: The authors declare that there are no conflicts of interest., (Copyright © 2021 Kang-Wen Xiao et al.)