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Contemporary studies in polarization multiplexing are hindered by the intrinsic orthogonality constraints of polarization states, which restrict the scope of multiplexing channels and their practical applications. This research transcends these barriers by introducing an innovative nonorthogonal polarization-basis multiplexing approach. Utilizing spatially varied eigen-polarization states within metaatoms, we successfully reconstruct globally nonorthogonal channels that exhibit minimal crosstalk. This method not only facilitates the generation of free-vector holograms, achieving complete degrees-of-freedom in three nonorthogonal channels with ultra-low energy leakage, but it also significantly enhances the dimensions of the Jones matrix, expanding it to a groundbreaking 10 × 10 scale. The fusion of a controllable eigen-polarization engineering mechanism with a vectorial diffraction neural network culminates in the experimental creation of 55 intricate holographic patterns across these expanded channels. This advancement represents a profound shift in the field of polarization multiplexing, unlocking opportunities in advanced holography and quantum encryption, among other applications. Recent advances in metasurface have expanded holographic capabilities. Here, authors introduce a nonorthogonal polarization multiplexing strategy using spatially varied eigen-polarization states in metaatoms to achieve 55-channel holography, unlocking the holographic information capacity.

In the domain of spectroscopy, miniaturization efforts often face significant challenges, particularly in achieving high spectral resolution and precise construction. Here, we introduce a computational spectrometer powered by a nonlinear photonic memristor with a WSe 2 homojunction. This approach overcomes traditional limitations, such as constrained Fermi level tunability, persistent dark current, and limited photoresponse dimensionality through dynamic energy band modulation driven by palladium (Pd) ion migration. The critical role of Pd ion migration is thoroughly supported by first-principles calculations, numerical simulations, and experimental verification, demonstrating its effectiveness in enhancing device performance. Additionally, we integrate this dynamic modulation with a specialized nonlinear neural network tailored to address the memristor’s inherent nonlinear photoresponse. This combination enables our spectrometer to achieve an exceptional peak wavelength accuracy of 0.18 nm and a spectral resolution of 2 nm within the 630–640 nm range. This development marks a significant advancement in the creation of compact, high-efficiency spectroscopic instruments and offers a versatile platform for applications across diverse material systems.

Objects with different shapes, materials and temperatures can emit distinct polarizations and spectral information in mid-infrared band, which provides a unique signature in the transparent window for object identification. However, the crosstalk among various polarization and wavelength channels prevents from accurate mid-infrared detections at high signal-to-noise ratio. Here, we report full-polarization metasurfaces to break the inherent eigen-polarization constraint over the wavelengths in mid-infrared. This recipe enables to select arbitrary orthogonal polarization basis at individual wavelength independently, therefore alleviating the crosstalk and efficiency degradation. A six-channel all-silicon metasurface is specifically presented to project focused mid-infrared light to distinct positions at three wavelengths, each with a pair of arbitrarily chosen orthogonal polarizations. An isolation ratio of 117 between neighboring polarization channels is experimentally recorded, exhibiting detection sensitivity one order of magnitude higher than existing infrared detectors. Remarkably, the high aspect ratio ~30 of our meta-structures manufactured by deep silicon etching technology at temperature −150 °C guarantees the large and precise phase dispersion control over a broadband from 3 to 4.5 μm. We believe our results would benefit the noise-immune mid-infrared detections in remote sensing and space-to-ground communications. Dispersive eigen-polarization engineering enabled polychromatic full-polarization control in mid-infrared.

To address the pronounced productivity heterogeneity among different well intervals of coalbed methane (CBM) wells in the Weizhou Syncline, as well as the lack of quantitative clarity regarding the respective contributions of geological and engineering factors to well productivity, a systematic analysis of the main productivity-controlling factors of CBM wells was conducted based on geological data from producing wells, hydraulic fracturing treatment parameters, and production dynamic data in the study area. On this basis, a coupled coal reservoir–fracture numerical simulation model was established to quantitatively evaluate the response of CBM productivity to key geological parameters, including porosity, permeability, coal seam thickness, and Langmuir parameters, as well as fracture geometric and flow parameters. Furthermore, multiple machine learning methods were employed to rank and cross-validate the relative importance of factors influencing CBM well productivity. The results indicate that within the parameter ranges representative of the study area, coal seam thickness, permeability, and Langmuir pressure exert a dominant control on cumulative gas production, constituting the primary controlling factors for CBM well productivity. The number of fractures and porosity are secondary influencing factors, and, under the combined effects of multiple factors, fracture geometry, fracture flow parameters, and reservoir pressure make relatively limited contributions to well productivity. These findings provide a quantitative basis and methodological reference for favorable target selection, fracturing parameter optimization, and efficient development of CBM blocks in the Weizhou Syncline and other regions with similar geological conditions.

Benefiting from the inherent capacity for detecting longer wavelengths inaccessible to human eyes, infrared photodetectors have found numerous applications in both military and daily life, such as individual combat weapons, automatic driving sensors and night-vision devices. However, the imperfect material growth and incomplete device manufacturing impose an inevitable restriction on the further improvement of infrared photodetectors. The advent of artificial microstructures, especially metasurfaces, featuring with strong light field enhancement and multifunctional properties in manipulating the light–matter interactions on subwavelength scale, have promised great potential in overcoming the bottlenecks faced by conventional infrared detectors. Additionally, metasurfaces exhibit versatile and flexible integration with existing detection semiconductors. In this paper, we start with a review of conventionally bulky and recently emerging two-dimensional material-based infrared photodetectors, i.e., InGaAs, HgCdTe, graphene, transition metal dichalcogenides and black phosphorus devices. As to the challenges the detectors are facing, we further discuss the recent progress on the metasurfaces integrated on the photodetectors and demonstrate their role in improving device performance. All information provided in this paper aims to open a new way to boost high-performance infrared photodetectors.

Cassava ( Crantz) is a major dual-purpose crop in tropical and subtropical regions, but its growth and yield are significantly constrained by abiotic stresses. Calmodulin-binding transcription activators (CAMTAs) are key regulators involved in plant development and stress responses. In this research, six genes ( ) were identified from the first telomere-to-telomere (T2T) genome assembly of cassava, and these genes are distributed on four chromosomes. These genes are divided into three different subfamilies based on phylogenetic relationships. Homology analysis shows that there is one pair of replication gene pairs. Analysis of cis-acting elements reveals that the promoter regions of the gene family contain cis-acting elements responsive to hormones, abiotic stresses, growth and development, and light. Through analysis of the expression patterns of in different tissues, are expressed in all tissues, among which and are mainly expressed in stems, while , , , and are mainly expressed in roots. qRT-PCR analysis shows that exhibit dynamic expression patterns under different abiotic stress treatments. Therefore, this study provides a certain reference basis for the research on the abiotic stress response mechanism of cassava and also provides potential genetic resources for the stress-resistant breeding of cassava.

This paper examines control and cooperation mechanisms for trans-regional air pollution using differential game theory. This study focuses on analyzing pollution control pathways in regions characterized by asymmetric economic development. Three models are constructed: the Nash non-cooperative game, the pollution control cost compensation mechanism, and the collaborative cooperation mechanism. These models are used to investigate optimal pollution control strategies for various regions. The findings indicate that the collaborative cooperation model substantially reduces pollution emissions and enhances overall benefits. Additionally, the pollution control cost compensation mechanism alleviates the burden of pollution control on less developed regions. Numerical analysis confirms the effectiveness of the proposed models and offers theoretical foundations and policy recommendations for regional cooperation in pollution prevention.

As an elementary particle, a photon that carries information in frequency, polarization, phase, and amplitude, plays a crucial role in modern science and technology. However, how to retrieve the full information of unknown photons in an ultracompact manner over broad bandwidth remains a challenging task with growing importance. Here, we demonstrate a versatile photonic slide rule based on an all-silicon metasurface that enables us to reconstruct incident photons’ frequency and polarization state. The underlying mechanism relies on the coherent interactions of frequency-driven phase diagrams which rotate at various angular velocities within broad bandwidth. The rotation direction and speed are determined by the topological charge and phase dispersion. Specifically, our metasurface leverages both achromatically focusing and azimuthally evolving phases with topological charges +1 and −1 to ensure the confocal annular intensity distributions. The combination of geometric phase and interference holography allows the joint manipulations of two distinct group delay coverages to realize angle-resolved in-pair spots in a transverse manner- a behavior that would disperse along longitudinal direction in conventional implementations. The spin-orbital coupling between the incident photons and vortex phases provides routing for the simultaneous identification of the photons’ frequency and circular polarization state through recognizing the spots’ locations. Our work provides an analog of the conventional slide rule to flexibly characterize the photons in an ultracompact and multifunctional way and may find applications in integrated optical circuits or pocketable devices.Metasurface-based photonic slide rule enables the simultaneous resolving of unknown photons’ wavelength and polarization state in mid-infrared.

HgCdTe avalanche photodiodes promise various fascinating applications due to the outstanding capability of detecting weak signals or even single photon. However, the underlying transport mechanisms of diverse dark current components are still unresolved at high reverse bias, thus limiting the development of high-performance devices. Here, we establish an accurate model to demonstrate the competitive mechanism between band-to-band and avalanche dark currents in positive-intrinsic-negative structures. Based on the high consistency between the simulated and measured results, we find that both components jointly dominate overall dark current but with a larger avalanche current. This breaks the conventional cognition that band-to-band dark current contributes the majority. With the guidance, we reconstruct an optimized device and achieve gain 1876 (6153) and dark current 10−10 (10−9) A at bias −10 (−10.5) V, respectively. Comparisons of dark current and gain with reported single-element devices further confirm the outstanding performance of our device.

The P-V and I-V curves of photovoltaic (PV) strings show multiple peaks when exposed to partial shading conditions (PSCs). The traditional maximum power point tracking (MPPT) method cannot track the global maximum power point (GMPP) due to the multi-peak characteristics, power fluctuation, and tracking speed. In this paper, a multi-peak PV MPPT method based on the honey badger algorithm (HBA) is proposed to track the GMPP in a localized shading environment. The performance of this method is also compared and analyzed with the traditional MPPT methods based on the perturbation observation (P&O) method and Particle Swarm Optimization (PSO) algorithm. The experimental results have proven that, compared with the MPPT methods based on P&O and PSO, the proposed multi-peak MPPT method based on the HBA algorithm has a faster tracking speed, higher tracking accuracy, and fewer iterations.