Bronze mou vessels appear in Shu tombs in south-west China during the Eastern Zhou period (c. 771-256 BC). Examination of these vessels reveals major changes in the supply of metal and alloying technology in the Shu State, throwing new light on the social impact of the Qin conquest and later unification of China.

The Huili area of Liangshan Prefecture has become an important gateway for the Jinsha Raver's middle reaches to Yunnan since the pre-Qin period.The Huili bronze culture shows a strong local primitive cultural foundation,and in the process of historical development,there have been exchanges and interactions with regional cultures,such as the south of the Jinsha River,to varying degrees.Bronze spearheads are bronze weapons commonly unearthed in bronze culture tombs in southwest China.They usually have killing and ritual functions.In addition,because of their unique typological characteristics,they can be used as special tools to distinguish cultural factors.Since the smelting of bronze is restricted by metallurgical technology and the supply of metal ore,the production technology of bronze weapons and the mineral resource are a good example for discussing the exchanges between the bronze culture in southwestern China and the surrounding cultures.In this context,in order to explore the provenance of bronze spearheads unearthed in Huili from the Warring States Period to the early Western Han Dynasty and their interaction with the surrounding culture,this study used a portable X-ray fluorescence spectrometer(pXRF),a multi-receiver inductively coupled plasma mass spectrometer(MC-ICP-MS)and other equipment to determine the composition and lead isotope ratios of four bronze spearheads unearthed from the Guojiabao cemetery.The bronze spearhead samples have willow-shaped leaves with a slight ridge in the middle.They have no ears on the sockets and have no pattern.This type of bronze spearhead is a typical local style.The scientific and technological analysis results show that spearhead samples'alloy composition varies greatly,including Cu-Pb alloy,Cu-Sn-Pb alloy and Cu-Pb-Sb alloy.However,the lead contents of all samples are higher than 2％,which means that the lead material was artificially added.The lead isotopic ratio analysis results revealed that the ore sources of this batch of copper spear samples were divided into two distinct groups:ordinary lead and highly radioactive lead.By comparing the lead isotope data of lead ore in the surrounding areas,it can be seen that the Huili bronze spearhead used the local lead materials and used the lead ore from the Jinshachang in Huize,northeastern Yunnan.From the Warring States Period to the Qin and Han Dynasties,the northeastern part of Yunnan belonged to the control area of the ancient Yelang bronze culture.It can be speculated that the Huili Bronze Culture and the Yelang Bronze Culture had close communication and connections.

Intelligent vision necessitates the deployment of detectors that are always-on and low-power, mirroring the continuous and uninterrupted responsiveness characteristic of human vision. Nonetheless, contemporary artificial vision systems attain this goal by the continuous processing of massive image frames and executing intricate algorithms, thereby expending substantial computational power and energy. In contrast, biological data processing, based on event-triggered spiking, has higher efficiency and lower energy consumption. Here, this work proposes an artificial vision architecture consisting of spiking photodetectors and artificial synapses, closely mirroring the intricacies of the human visual system. Distinct from previously reported techniques, the photodetector is self-powered and event-triggered, outputting light-modulated spiking signals directly, thereby fulfilling the imperative for always-on with low-power consumption. With the spiking signals processing through the integrated synapse units, recognition of graphics, gestures, and human action has been implemented, illustrating the potent image processing capabilities inherent within this architecture. The results prove the 90% accuracy rate in human action recognition within a mere five epochs utilizing a rudimentary artificial neural network. This novel architecture, grounded in spiking photodetectors, offers a viable alternative to the extant models of always-on low-power artificial vision system.

Surprising combinations of bronze vessels with multiple cultural elements have been unearthed in Shu tombs in southwestern China, indicating a significant connection with the middle and lower reaches of the Yangtze River. However, there is currently no comprehensive evidence for the provenance of these foreign style vessels, and little emphasis has been given to the diachronic changes in the interaction between Shu culture and its surroundings. This article investigates the bronze vessels unearthed from the Shuangyuan Village Cemetery in Chengdu during the Eastern Zhou Dynasty and aims to deeply reveal the production and exchange of bronze vessels unearthed from Shuangyuan Village Cemetery from the perspective of lead sources through typological analysis and scientific analysis. The study clarified the ages of the local style Shu culture vessels and foreign style vessels, and the latter exhibited a strong influence of the Chu and Yue cultures. Lead isotope analysis shows that the lead source characteristics of foreign style vessels are consistent with those of vessels from Chu-Yue culture at the same time, and they may be imported from Chu directly. The specific interaction modes of Shu and Chu underwent a clear transformation during the middle Warring States period.

Background: Bronze knives, which have been excavated in large quantities and acquired hierarchical significance, are essential artifacts in Shu State in Southwest China. Building upon previous typological analyses of bronze knives, it is hypothesized that Shu culture may have imported foreign-style bronze knives. However, further demonstration of the provenance of metal materials, the typology of knives, and the cultural exchange necessitates a comprehensive examination through the lens of scientific analysis. The purpose of this study is to investigate the differences in the manufacturing processes and metal resources of Shu bronze knives with various cultural styles and whether bronze knives in the foreign styles were imported or locally imitated. Methods: In this study, the typology, portable X-ray fluorescence spectrometry and multi-collector inductively coupled plasma mass spectrometry were used to analyze twenty-four bronze knives unearthed from Shuangyuan cemetery, a cemetery of the Eastern Zhou Dynasty in Chengdu City, Sichuan Province, Southwest China. Results: The results of the study show that the knives of Shuangyuan Cemetery can be classified typologically into five types, encompassing both local and foreign styles. The predominant alloy composition of these knives is lead-tin bronze, characterized by a notably high tin content. Lead isotope ratios indicate that metal materials from the South China geochemical province and Yangtze geochemical province were mainly used to manufacture the bronze knives unearthed from the Shu state Conclusion: While the majority of foreign-style knives with ring-shaped heads were likely imported from neighboring regions like Chu state, distinctively styled type D and type E bronze knives appear to have been locally imitated by the Shu, showcasing a blend of external influences and indigenous innovation. The combination of typology and scientific analysis of the bronze knife may shed new light on the study of the Shu culture of the Eastern Zhou period.

Inverted perovskite solar cells (PSCs) are preferred for tandem applications due to their superior compatibility with diverse bottom solar cells. However, the solution processing and low formation energy of perovskites inevitably lead to numerous defects at both the bulk and interfaces. We report a facile and effective strategy for precisely modulating the perovskite by incorporating AlOx deposited by atomic layer deposition (ALD) on the top interface. We find that Al3+ can not only infiltrate the bulk phase and interact with halide ions to suppress ion migration and phase separation but also regulate the arrangement of energy levels and passivate defects on the perovskite surface and grain boundaries. Additionally, ALD-AlOx exhibits an encapsulation effect through a dense interlayer. Consequently, the ALD-AlOx treatment can significantly improve the power conversion efficiency (PCE) to 21.80 % for 1.66 electron volt (eV) PSCs. A monolithic perovskite-silicon TSCs using AlOx-modified perovskite achieved a PCE of 28.5 % with excellent photothermal stability. More importantly, the resulting 1.55 eV PSC and module achieved a PCE of 25.08 % (0.04 cm2) and 21.01 % (aperture area of 15.5 cm2), respectively. Our study provides an effective way to efficient and stable wide-band gap perovskite for perovskite-silicon TSCs and paves the way for large-area inverted PSCs.

To maximize the power conversion efficiency (PCE) and stability of perovskite/silicon tandem solar cells (TSCs), high‐performance and stable perovskite top cells with wide‐bandgaps are required. A 2D/3D wide‐bandgap perovskite with a bandgap of 1.69 eV using 1H‐1,2,4‐triazole‐1‐carboximidamide (1‐TzFACl) as a spacer is developed. The 2D/3D wide‐bandgap perovskite shows better film quality, enhanced crystallinity, suppressed nonradiative recombination, and significantly improved phase stability. Its initial PCE (21.58%) remains above 87% after 1560 h of continuous illumination due to the insertion of Cl − in the perovskite lattice. A monolithic two‐terminal perovskite/silicon TSC achieves a PCE of 25.66% with high light stability. This work provides an ingenious strategy to restrain the phase segregation in wide‐bandgap perovskites, leading to effective and stable perovskite/silicon TSCs.

A considerable efficiency gap exists between large-area perovskite solar modules and small-area perovskite solar cells. The control of forming uniform and large-area film and perovskite crystallization is still the main obstacle restricting the efficiency of PSMs. In this work, we adopted a solid–liquid two-step film formation technique, which involved the evaporation of a lead iodide film and blade coating of an organic ammonium halide solution to prepare perovskite films. This method possesses the advantages of integrating vapor deposition and solution methods, which could apply to substrates with different roughness and avoid using toxic solvents to achieve a more uniform, large-area perovskite film. Furthermore, modification of the NiO x /perovskite buried interface and introduction of Urea additives were utilized to reduce interface recombination and regulate perovskite crystallization. As a result, a large-area perovskite film possessing larger grains, fewer pinholes, and reduced defects could be achieved. The inverted PSM with an active area of 61.56 cm 2 (10 × 10 cm 2 substrate) achieved a champion power conversion efficiency of 20.56% and significantly improved stability. This method suggests an innovative approach to resolving the uniformity issue associated with large-area film fabrication.

Spiking neural networks (SNNs), as a biology-inspired method mimicking the spiking nature of brain neurons, is a promising energy-efficient alternative to the traditional artificial neural networks (ANNs). The energy saving of SNNs is mainly from multiplication free property brought by binarized intermediate activations. In this paper, we proposed a Multiple Threshold (MT) approach to alleviate the precision loss brought by the binarized activations, such that SNNs can reach higher accuracy at fewer steps. We evaluate the approach on CIFAR10, CIFAR100 and DVS-CIFAR10, and demonstrate that MT can promote SNNs extensively, especially at early steps. For example, With MT, Parametric-Leaky-Integrate-Fire(PLIF) based VGG net can even outperform the ANN counterpart with 1 step.

Rapid development of modern science and technology has prompted explosive growth of data volumes, especially the visual information, which brings heavy pressure on information processing and computation. The classic technical route to improve the computation power of image processing units by reducing the critical dimension of the transistors according to Moore's law gradually fails due to the physical limit of transistors' footprint and the separated architectures. Inspired by human vision systems, retina-like photodetectors that mimic their spatial and temporal properties have attracted widespread attention. These developed architectures enable the early data processing in- or near-sensor, significantly reducing the computing power required in the back end. Herein, a comprehensive review on bioinspired photodetectors that possess the spatial and temporal properties of biological vision is provided. The properties of retina are summarized and presented first. Basic structure design and operation mechanism of those photodetectors with spatial properties of retina (including the distribution of receptive fields and the shape of the hemisphere) and temporal properties of retina (including the memory properties enabled learning and the light intensity adaptation) are reviewed thoroughly. Eventually, challenges and future perspectives are commented and provided to facilitate the rapid development of in- or near-sensor computing photodetectors.

The photovoltaic effect can directly harvest solar energy by converting optical signals into current without external bias, and thus is a practical and sustainable approach for low-power, high-linearity, and gate-switchable optoelectronic devices.

To take full use of the outstanding photoelectric properties of two-dimensional transition-metal dichalcogenides (2D TMDs), techniques for tuning their band gaps have been developed, among which defect engineering is found to be an effective way for broadband spectrum photodetection. Methods like pulsed laser deposition, thermal annealing, electron/proton beam etching, etc., can effectively reduce band gaps by introducing vacancy defects into TMDs, but they face the problems of high costs, uneven distribution of prepared defects, and unstable material properties. To solve these problems, we proposed a two-step strategy from "alloy synthesis" to "vacancy introduction". Taking use of the bond energy differences between W-Se and W-Te in ternary alloy, WSe2(1-x)Te2x samples with homogeneous distributions of Se and Te were first synthesized, and then vacancy defects could be introduced through controllable release of Te atoms during a hydrogen-assisted annealing process, resulting in similar to 4.1% vacancy defects with uniform distribution. A 910 nm photoluminescence (PL) peak appears in the annealed WSe2(1-x)Te2x, exhibiting a 110 nm red shift from the 800 nm peak of the unannealed alloy. Photoresponse of up to 1000 nm of the corresponding device verifies that a broadband spectrum detection TMD device has been successfully achieved in this study.

Searching van der Waals ferroic materials that can work under ambient conditions is of critical importance for developing ferroic devices at the two-dimensional limit. Here we report the experimental discovery of electric-field-induced reversible antiferroelectric (AFE) to ferroelectric (FE) transition at room temperature in van der Waals layered α-GeSe, employing Raman spectroscopy, transmission electron microscopy, second-harmonic generation, and piezoelectric force microscopy consolidated by first-principles calculations. An orientation-dependent AFE-FE transition provides strong evidence that the in-plane (IP) polarization vector aligns along the armchair rather than zigzag direction in α-GeSe. In addition, temperature-dependent Raman spectra showed that the IP polarization could sustain up to higher than 700 K. Our findings suggest that α-GeSe, which is also a potential ferrovalley material, could be a robust building block for creating artificial 2D multiferroics at room temperature.

γ-indium selenide (InSe) is a van der Waals semiconductor and holds great potentials for low-energy-consumption electronic and optoelectronic devices. Herein, we investigated the hydrostatic pressure engineered near-infrared (NIR) light emission of mechanically exfoliated γ-InSe crystals using the diamond anvil cell (DAC) technique. A record-wide spectral tuning range of 185 nm and a large linear pressure coefficient of 40 nm GPa-1 were achieved for spontaneous emissions, leading to ultrabroadband microlasing spectrally ranging from 1022 to 911 nm. This high emission tunability can be attributed to the compression of the soft intralayer In-Se bonds under high pressure, which suppressed the band gap shrinkage by increasing the interlayer interaction. Furthermore, two band gap crossovers of valence (direct-to-indirect) and conduction bands were resolved at approximately 4.0 and 7.0 GPa, respectively, resulting in pressure-sensitive emission lifetime and intensity. These findings pave the pathways for pressure-sensitive InSe-based NIR light sources, sensors and so on.

An ancient and well-developed late Shu culture was discovered in the Sichuan Basin in southwest China. For a long time, the evolution of the resource utilization of the late Shu culture has been shrouded in mystery, and it is under considerable controversy when it comes to the relationship between the late Shu culture and the Chu culture of the middle reaches of the Yangtze River. Therefore, in this paper, bronze poleaxes with characteristics of different periods, which were excavated from the Shuangyuan cemetery of the Eastern Zhou Dynasty in the Chengdu Plain, were studied by archaeological typology, portable X-ray fluorescence spectrometry (pXRF), and multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). In contrast to previous studies, this paper achieves a further distinction among the mineral sources of a very short historical period within the long history of the late Shu culture by analyzing the local bronze poleaxes. The results show that the Shu ancestors used the same kind of lead material from the early Warring States Period to the early stage of the middle Warring States Period. However, the mineral sources of the late Shu culture underwent a significant shift in the late stage of middle Warring States Period, which was closely related to the historical background of cultural exchanges between Chu culture and Shu culture. This work indicates that the exchange between Shu and Chu gradually deepened over time during the Warring States Period.

As typical artifacts of the Ba-Shu culture, bronze dagger-axes have always been highly valued by academia. Underneath-blade bronze dagger-axes were utilized widely in both the Central Plains and southwest China. However, opinions differ on whether these underneath-blade bronze dagger-axes which excavated from Ba-Shu culture were produced locally. Combined with archaeological typology study, p-XRF and MC-ICP-MS were used to analyze 12 underneath-blade bronze dagger-axes unearthed from Shuangyuan Village Site, an Eastern Zhou cemetery in Chengdu city, Sichuan Province, Southwest China in order to investigate the cultural exchange and integration centered on the Shu culture. The composition results show that the majority of samples were made from copper, tin, and lead ternary alloy. The data on lead isotopes indicate that underneath-blade bronze dagger-axes have different mineral sources. The lead isotope ratio 206 Pb/ 204 Pb of 18.3 can draw the conclusion to be used as one of the bases for judging that underneath-blade bronze dagger-axes originated in the Chengdu Plain or the Central Plains which was consistent with the typology. The southern China lead materials of underneath-blade bronze dagger-axes in the Ba-Shu and Central Plains style probably came from southern Sichuan; while the rest of underneath-blade bronze dagger-axes in the Central Plains style might use lead materials in the western Hunan-western Hubei area. The Shu culture which was represented by Shuangyuan Village Site in Chengdu Plain during the Eastern Zhou Dynasty had close cultural communication with the Central Plains and Chu cultures. This study reveals that Ba-Shu had a direct exchange of minerals or metal products with the Central Plains and Chu, as well as an imitation based on the identification of the foreign culture and the belief in the local Shu cultural traditions.

Willow-leaf shaped sword is a kind of exclusive bronze weapon popular only in the states of Ba and Shu during the Eastern Zhou Dynasty (770-256 BC). Its prototype may originate from Central Asia and India and is a typical example of a trans-regional and cross-cultural artifact. Here, we present a scientific study of willow-leaf shaped swords of Shu State from the Shuangyuan Village Cemetery, Chengdu, by pXRF and MC-ICP-MS, and attempted to argue for the improvement and integration of weapon production in Shu by characterizing its elemental composition and lead isotopic signature. The results show that there is a significant difference in the tin content and lead material source between the Ba and Shu bronze swords. This feature can be applied as an important indicator to distinguish willow-leaf shaped swords from Ba and Shu, especially when the appearances are almost confused. The alloy formula of the Shu bronze sword was influenced by the bronze-making technology of Chu and other states. Combining the published lead isotope data of the willow-shaped bronze swords, it can be inferred that Shu State has produced bronze weapons with considerable frequency and in many batches, which was a major motivation for triggering faster progress in its craft.

The interfacial tunable band alignment of heterostructures is coveted in device design and optimization of device performance. As an intentional approach, alloying allows band engineering and continuous band‐edge tunability for low‐dimensional semiconductors. Thus, combining the tunability of alloying with the band structure of a heterostructure is highly desirable for the improvement of device characteristics. In this work, the single‐step growth of alloy‐to‐alloy (MoS2(1‐x)Se2x/SnS2(1‐y)Se2y) 2D vertical heterostructures is demonstrated. Electron diffraction reveals the well‐aligned heteroepitaxial relationship for the heterostructure, and a near‐atomically sharp and defect‐free boundary along the interface is observed. The nearly intrinsic van der Waals (vdW) interface enables measurement of the intrinsic behaviors of the heterostructures. The optimized type‐II band alignment for the MoS2(1‐x)Se2x/SnS2(1‐y)Se2y heterostructure, along with the large band offset and effective charge transfer, is confirmed through quenched PL spectroscopy combined with density functional theory calculations. Devices based on completely stacked heterostructures show one or two orders enhanced electron mobility and rectification ratio than those of the constituent materials. The realization of device‐quality alloy‐to‐alloy heterostructures provides a new material platform for precisely tuning band alignment and optimizing device applications.

Among the IV-VI compounds, GeSe has wide applications in nanoelectronics due to its unique photoelectric properties and adjustable band gap. Even though modulation of its physical characteristics, including the band gap, by an external field will be useful for designing novel devices, experimental work is still rare. Here, we report a detailed anisotropic Raman response of GeSe flakes under uniaxial tension strain. Based on theoretical analysis, the anisotropy of the phonon response is attributed to a change in anisotropic bond length and bond angle under in-plane uniaxial strain. An enhancement in anisotropy and band gap is found due to strain along the ZZ or AC directions. This study shows that strain-engineering is an effective method for controlling the GeSe lattice, and paves the way for modulating the anisotropic electric and optical properties of GeSe.

2D van der Waals heterostructures (vdWHs) offer tremendous opportunities in designing multifunctional electronic devices. Due to the ultrathin nature of 2D materials, the gate-induced change in charge density makes amplitude control possible, creating a new programmable unilateral rectifier. The study of 2D vdWHs-based reversible unilateral rectifier is lacking, although it can give rise to a new degree of freedom for modulating the output state. Here, a InSe/GeSe vdWH-FET is constructed as a gate-controllable half wave rectifier. The device exhibits stepless adjustment from forward to backward rectifying performance, leading to multiple operation states of output level. Near-broken band alignment in the InSe/GeSe vdWH-FET is a crucial feature for high-performance reversible rectifier, which is shown to have backward and forward rectification ratio of 1:38 and 963:1, respectively. Being further explored as a new bridge rectifier, the InSe/GeSe device has great potential in future gate-controllable alternating current/direct current convertor. These results indicate that 2D vdWHs with near-broken band alignment can offer a pathway to simplify the commutating circuit and regulating speed circuit.