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To determine the emplacement age, petrogenesis, and geodynamic setting of the Xizhelimu diorite in Keyouzhongqi, Inner Mongolia of northeastern China, a detailed study of the petrography geochronology, and whole-rock geochemistry has been conducted. Geological and petrographic studies show that the Xizhelimu diorite is zoned: the central lithofacies zone is composed of medium-fine-grained monzodiorite and quartz diorite, and the marginal lithofacies zone is fine-grained diorite. The zircon U-Pb dating results show that the ages of the central and marginal facies are 133.5 [+ or -] 1.9 and 133.4 [+ or -] 1.4 Ma, respectively. The whole-rock rare earth and trace element characteristics of the Xizhelimu diorite show an O-type adakite affinity. Combining the analysis of zircon Hf isotope composition ([[epsilon].sub.Hf(t)] values of +7.7 to +10.0), the geochemical features of whole rock, and the results of partial melting modeling, we suggest that the parental magma of the Xizhelimu diorite was derived from the partial melting of altered oceanic crust mixing with subducting sediments at shallow depths. In the early stage of early Cretaceous, the Xizhelimu diorite originated in an extensional setting, mainly related to the closure of the western part of the Mongol-Okhotsk Ocean. The upwelling asthenospheric flow in this extensional setting induced partial melting of the paleo-oceanic crust to form the parental magma of the Xizhelimu diorite. Key words: Early Cretaceous diorite, O-type adakite, tectonic setting, the southern Great Xing'an Range, 1. Introduction Adakites have been widely studied since they were proposed. Initially adakites were broadly denned as rocks formed by the partial melting of subducted oceanic slabs, with unique geochemical [...]

As a non-toxic and non-polluting semiconductor material, Mg2Si/Si has great potential for application in the field of visible and near-infrared photo detection due to its excellent physical properties. In this work, Mg2Si/Si thin films were prepared by magnetron sputtering of Mg film on Si substrate followed by an annealing process. The effects of annealing temperature and annealing time on the growth of Mg2Si/Si thin film were studied, and large-area high-quality Mg2Si/Si thin film was prepared at an annealing temperature of 420 °C and an annealing time of 8 h. To improve the quality of Mg2Si/Si thin film and the performance of the Mg2Si/Si heterojunction photodetector, nanostructures were fabricated in the surface of the Si substrate by using an anodic aluminum oxide (AAO) mask and a plasma etching process. The nanostructures enable the Mg film and Si substrate to have an increased contact area and facilitate the solid-phase reaction between Mg and Si to grow Mg2Si/Si film. For the visible and near-infrared bands, the integration of nanostructures provides the photodetectors with a 173–402% improvement in responsivity and a 111–281% improvement in specific detectivity compared to normal Mg2Si/Si heterojunction devices. The maximum responsivity of the device is 183 mA W−1, and the specific detectivity is enhanced to 9.43 × 109 Jones at 1064 nm. This work provides a new approach for the development and application of Si-based Mg2Si/Si film and Mg2Si/Si heterojunction photodetectors with high performance. [ABSTRACT FROM AUTHOR]

[Display omitted] • Early Cretaceous magmatism (132–121 Ma) from the Southern Great Xing'an Range. • The transcrustal magmatic system recorded by rock assemblages. • The peralkaline magma derived by interaction of extracted melts and alkali fluids. The generation and evolution of crustal-scale magmatic systems are important in revealing the continental crust differentiation. In the Bayangeer-Aliwula area of Inner Mongolia, metaluminous–peraluminous–peralkaline rock assemblages provide a rare opportunity to evaluate Early Cretaceous magmatic systems. This study presents new geochemical data, including whole-rock and zircon geochemistry, zircon U–Pb dating, and Hf–O isotopic analysis of rocks formed between 132 and 121 Ma. The metaluminous rocks exhibit low SiO 2 (55.35–65.65 wt%), low Rb/Sr (0.08–0.24) and (La/Yb) N (4.88–7.58) ratios, and positive ε Hf (t) values (+4.9 to +8.7). These features, along with enrichment in large-ion lithophile elements and depletion in Nb and Ta, suggest formation via partial melting of fluid-metasomatised lithospheric mantle. By contrast, peraluminous rocks have high SiO 2 (69.37–80.58 wt%), a high differentiation index (DI = 88–95), and Fe-index (0.84–0.95), resembling highly fractionated I-type granites. They show high Rb/Sr (0.77–3.35) and (La/Yb) N (5.79–22.75) ratios, and positive ε Hf (t) values (+6.7 to +10.8), combined with the modelling results, indicating origin from partial melting of K-rich mafic lower crust followed by magma fractionation. Peralkaline rocks display typical ferroan A-type granite characteristics (Zr + Nb + Ce + Y = 906–4292 ppm; Fe-index = 0.96–0.99), with high SiO 2 (74.02–77.50 wt%), high Rb/Sr (6.17–121.38), and (La/Yb) N ratios (2.19–17.72), and positive ε Hf (t) values (+3.1 to +9.6). Zircon geochemistry characteristics suggest that peralkaline and peraluminous felsic melts are different batches extracted from the same magma reservoir. Further analysis, including hyperbola diagrams and zircon oxygen isotope compositions, suggests peralkaline magma formation through the mixing of altered oceanic crust fluids and peraluminous melts after melt extraction. During Early Cretaceous, the transcrustal magmatic system provides a reasonable explanation for the petrogenesis of various contemporaneous rocks in the study area in southern Great Xing'an Range. [ABSTRACT FROM AUTHOR]

The Solonker-Xar Moron-Changchun-Yanji Suture Zone is the result of the final closure of the Paleo-Asian Ocean (PAO). However, the closure time of the PAO in Northeast China remains controversial. The Hunchun area is located in the easternmost part of the Solonker-Xar Moron-Changchun-Yanji Suture Zone. Tectonism and magmatism in the Hunchun area can provide important information for understanding the late-stage evolution of the PAO. In this study, our zircon U-Pb ages show that the granodiorites and diorites in the Hunchun were formed at 282.3–251.4 Ma. This geochronological evidence suggests prolonged Permian magmatism in the Hunchun area. Whole-rock geochemistry, zircon trace, and Lu-Hf isotope data show that all the intrusive rocks are mainly calc-alkaline series to arc tholeiite series. Granodiorites are I-type granites formed by the partial melting of juvenile lower crust derived from the mantle. Diorites show similar characteristics to the sanukitic high-Mg diorite and are formed by the partial melting of the depleted mantle metasomatized by subduction sediments and/or slab-derived fluids. These results indicate that the Permian diorites and granodiorites in the Hunchun area formed in an active continental margin setting related to the subduction of the PAO plate. Significantly, sudden changes in the whole-rock Sr/Y and (La/Yb)N ratios and zircon εHf(t) values are observed in the Late Permian-Early Triassic igneous rocks in the eastern Central Asian Orogenic Belt (CAOB). This indicates that the final closure of the PAO in Northeast China likely occurred in the Late Permian-Early Triassic. [ABSTRACT FROM AUTHOR]

In the domain of high‐performance short‐wave infrared (SWIR) photodetection and imaging, existing technologies predominantly utilize single‐crystal germanium and III‐V semiconductors. Despite their efficacy, these materials are encumbered by laborious synthesis and complex fabrication demands. In this study, the synthesis of large‐area, high‐crystallinity Se0.2Te0.8 thin films through a CMOS‐compatible vacuum thermal evaporation process is reported. A high‐speed, broad‐spectrum photodetector engineered with an innovative Gr/Se0.2Te0.8/GaAs vertical heterostructure is presented, which capitalizes on the augmented carrier mobility and employs graphene innovatively as both a carrier collection interface and an electrode. This configuration facilitates a remarkably swift response time of 800 ns/1 µs at the crucial 1310 nm wavelength for optical communications. Moreover, the fabrication of a 5 × 5 array device demonstrates substantial SWIR imaging capabilities at ambient conditions, marking a paradigm shift in uncooled infrared imaging and communication technologies. This work not only extends the boundaries of SWIR photodetector performance but also underscores the potential of novel material systems in high‐speed optical applications. [ABSTRACT FROM AUTHOR]

Abstract Background Field studies from 2011 onwards have demonstrated the presence of a breeding population of Yellow Wagtails (Motacilla flava) in the Xinjiang Uygur Autonomous Region, China that is phenotypically distinct from known subspecies occurring in Asia. Here we describe the plumages and vocalisations of this population and discuss its taxonomic status. Methods The analysis of plumage is based on field studies and photos available online. Recordings of vocalisations are compared with recordings from other Yellow Wagtail populations, and differences are analysed based on sonograms. Mitochondrial DNA from one individual is compared to other Yellow Wagtail taxa. Results Unlike M. flava subspecies breeding in or near Xinjiang, males in the studied population show a blue-grey head without prominent white supercilium, being most similar to the widely disjunct M. f. cinereocapilla. They differ from the similarly widely allopatric M. f. thunbergi, which might occur as a migrant or vagrant in Xinjiang, by on average cleaner yellow breast and more extensive white on the throat, and from the widely disjunct M. f. plexa and M. f. macronyx, which might also occur on migration in that area, by softer contact calls and slower pace of song. Females are similar to female M. f. feldegg in plumage. The mitochondrial ND2 tree shows the single sample from Xinjiang to be nested in the clade of western Yellow Wagtail taxa. Conclusion We discuss whether the Xinjiang breeding population could represent an intergrade between subspecies breeding nearby, or whether it is better regarded as a separate as yet unrecognized subspecies. We argue that the localization of its apparent range in relation to other subspecies along with fairly consistent male and female plumages suggest that it is more likely to represent an undescribed taxon, but conclude that more research is needed to firmly establish its status.

Photothermoelectric (PTE) detectors, renowned for their ultra-broadband photodetection capabilities at room temperature without requiring an external power supply, are pivotal for advancing infrared and terahertz detection technologies. Despite significant advancements with high-performance PTE detectors utilizing low-dimensional nanomaterials like graphene, persistent challenges such as low optical absorption efficiency and the complexities of scaling integration processes continue to restrict enhancements in device integration and wavelength scalability. Here, we introduce a high-performance long-wave infrared (LWIR) PTE photodetector, integrating a resonant nanophotonic structure with a photothermoelectric nanofilm. This detector capitalizes on the synergistic interactions between metasurfaces and photonic resonators, achieving an unprecedented peak absorption rate of 98.6% across a critical operational range of 8–20 μm. Our pioneering integration of the perfect absorber with photothermoelectric materials facilitates the fabrication of a self-powered detector, showcasing a responsivity of 0.388 mA W−1, a rapid response time of 10 ms, and outstanding air stability. This research not only validates the feasibility of room-temperature, highly sensitive, and broadband photodetectors but also introduces a scalable approach that can be extended to other spectral regions through straightforward modifications to the resonant wavelength of the absorber. [ABSTRACT FROM AUTHOR]

Polarization‐sensitive photodetectors have garnered significant interest due to their promising applications in navigation, remote sensing, and optical communication. However, conventional polarized light detectors relying on optical filters face challenges due to intricate fabrication and calibration procedures. While structures based on in‐plane anisotropic 2D materials have the potential to offer viable solutions for polarization detection, achieving both low power consumption and high performance remains challenging. Herein, a self‐powered anisotropic/isotropic ReS2/SnSe2 van der Waals (vdWs) heterojunction detector with high‐performance features is constructed. This device exhibits outstanding photovoltaic (PV) performance across a wide spectral range from 405 to 850 nm without bias, featuring excellent responsivity (0.966 A W−1) and specific detectivity (1.47 × 1010 Jones) under 650 nm laser illumination. Moreover, benefiting from the built‐in electric field that promotes carrier separation and extremely low dark current, the device shows fast response time (230/240 µs) with an on/off ratio of up to 104. Furthermore, the ReS2/SnSe2 photodetector demonstrates exceptional polarization encoding performance, with a polarization ratio of 1.56 under 650 nm illumination, opening up new possibilities in optical communication technology development. This research provides a novel and viable option for developing energy‐efficient and high‐performance polarization‐sensitive detectors. [ABSTRACT FROM AUTHOR]

The Kunduleng granite hosts one of several significant uranium anomalies within the southern Great Xing'an Range, NE China. Whole-rock geochemistry and mineral chemistry data, along with the zircon U-Pb-Hf isotope have been used to constrain the petrogenesis of this granitic intrusion and the origin of the uranium anomaly. Microscopically, quartz, alkali-feldspar, and plagioclase are the essential mineral constituents of the granite, with minor biotite, while monazite, apatite, xenotime, and zircon are accessory minerals. Geochemically, the silica- and alkali-rich granites show a highly fractionated character with "seagull-shaped" REE patterns and significant negative anomalies of Ba and Sr, along with low Zr/Hf and Nb/Ta ratios. The granite has positive zircon εHf(t) values ranging from +12.7 to +14.5 and crustal model ages (TDM2) of 259–376 Ma, indicating a Paleozoic juvenile crustal source. Uraninite and brannerite are the main radioactive minerals responsible for the uranium anomaly within the Kunduleng granite. Uraninite presents well-developed cubic crystals and occurs as tiny inclusions in quartz and K-feldspar with magmatic characteristics (e.g., elevated ThO2, Y2O3, and REE2O3 contents and low CaO, FeO, and SiO2 concentrations). The calculated U-Th-Pb chemical ages (135.4 Ma) are contemporaneous with the U-Pb zircon age (135.4–135.6 Ma) of the granite, indicating a magmatic genesis for uraninite. The granites are highly differentiated, and extreme magmatic fractionation might be the main mechanism for the initial uranium enrichment. Brannerite is relatively less abundant and typically forms crusts on ilmenite and rutile or it cements them, representing the local redistribution and accumulation of uranium. [ABSTRACT FROM AUTHOR]

In this paper, we present a rigorous coupled-wave analysis (RCWA) of absorption enhancement in all-silicon (Si) photodiodes with integrated hole arrays of different shapes and dimensions. The RCWA method is used to analyze the light propagation and trapping in the photodiodes on both Si-on-insulator (SOI) and bulk Si substrates for the datacom wavelength at about 850 nm. Our calculation and measurement results show that funnel-shaped holes with tapered sidewalls lead to low back-reflection. A beam of light undergoes a deflection subsequent to the diffraction in the hole array and generates laterally propagating waves. SOI substrates with oxide layers play an important role in reducing the transmission loss, especially for deflected light with higher-order diffraction from the hole array. Owing to laterally propagating modes and back-reflection on the SiO2 film, light is more confined in the thin Si layer on the SOI substrates compared to that on the bulk Si substrates. Experimental results based on fabricated devices support the predictions of the RCWA. Devices are designed with a 2-μm-thick intrinsic layer, which ensures ultrafast impulse response (full-width at half-maximum) of 30 ps. Measurements for integrated photodiodes with funnel-shaped holes indicate an enhanced external quantum efficiency of more than 55% on the SOI substrates. This represents more than 500% improvement compared to photodiodes without integrated phototrapping nanoholes.