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Opto-electrical properties of MgxZn1−xO can be tuned by adjusting the value of x, but phase separation occurs when x is greater than 0.4. Hydrogen acts as a shallow donor in MgxZn1−xO and can play an important role in tuning the opto-electrical properties in a way that avoids phase separation. Mg0.1Zn0.9O (MZO) films were prepared at different hydrogen partial pressures and their structures and properties were studied. XRD results show that the MZO film has a wurtzite structure with a preferential orientation along the c-axis, but the crystallinity declines with increasing hydrogen partial pressure. Stress in the MZO film changes from tensile to compressive as the hydrogen partial pressure increases. Increasing the hydrogen partial pressure improves the conductivity and increases the optical bandgap, but the electronic affinity of MZO decreases, according to ultraviolet photoelectron spectroscopy results. These key parameters were used to simulate a device with a TCO/MZO/CdTe/ZnTe:Cu type structure, in which TCO is the transparent conductive oxide. The highest efficiency of 17.37% was achieved when the electron affinity of the MZO film was 3.71 eV, corresponding to a spark-like band offset of 0.29 eV at the MZO/CdTe interface. These results suggest that the electron affinity of MZO can be tuned to achieve an optimal band alignment in the device. [ABSTRACT FROM AUTHOR]

From 2000 to 2015, China’s industry and economy developed rapidly, while at the same time, it became the world’s largest carbon emitter. China’s development trajectory in the 15 years since 2000 is similar to Japan’s in the 1960s and 1980s. This paper used the Logarithmic mean Divisa index (LMDI) method to estimate the impact factors of carbon emissions in China from 2000-2015 and in Japan from 1971-1986. The differences and commonalities of carbon emissions between the two countries in the two periods were discussed by comparing the driving factors of carbon emissions. On this basis, corresponding policies were provided in this paper.

Blade coating offers a low-cost production method for fabricating perovskite thick-film x-ray detectors. However, due to the preferential nucleation at the gas–liquid interface of a perovskite solution, high-quality perovskite thick films are in such a dilemma, sacrificing either the density of the thick film by forming a porous structure or the thickness of the film through depositing a compact structure. The porous structure will lead to carrier recombination and ion migration while low thickness will cause insufficient x-ray absorption, which will increase the dark current or reduce the sensitivity of the corresponding x-ray detector. In the present work, a scalable ferroelectric dipole–methylamine lead iodide (MAPbI3) coupled x-ray detector is proposed, where the x-ray photoconductor in situ formed on indium tin oxide shows a dense fibrous mesoscopic structure oriented along the charge-carriers transport direction. It is demonstrated that ferroelectric dipoles promise not only strong coupling effects with MAPbI3, driving better crystallinity and denser assemblies, but also excellent passivation to MAPbI3 interfaces, decreasing trap-state densities, leading to improved direct x-ray detection performance. In addition, the enhanced operational stability of the corresponding device suggests a strategy of introducing the localized polarization field for stable perovskite direct x-ray detectors. [ABSTRACT FROM AUTHOR]

Accurate vestibule segmentation for CT images is of great significance for the clinical diagnosis of congenital ear malformations and cochlear implant. However, it is still a challenging task due to extremely small size and irregular shape of vestibule. Here, a vestibule segmentation network for CT images is proposed under the basic encoder‐decoder framework. Firstly, a residual block based on channel attention mechanism, named Res‐CA block, is designed to guide the network to enhance the important features for the segmentation tasks while suppressing the irrelevant ones. And then, a global context‐aware pyramid feature extraction (GCPFE) module is proposed to capture multi‐receptive‐field global context information. Finally, active contour with elastic (ACE) loss function is adopted to guide network learning more detailed information of the boundary. Furthermore, deep supervision (DS) mechanism is employed to locate the boundaries finely, improving the robustness of the network. The experiments are conducted on the self‐established VestibuleDataset and UHRCT‐Dataset, as well as publicly available retinal dataset, namely DRIVE, to comprehensively verify the robustness and generalization capability of the proposed segmentation network. The experimental results show that the proposed network can achieve a superior performance. [ABSTRACT FROM AUTHOR]

A large lateral photovoltaic effect (LPE) with a fast optical response time is necessary to develop high-performance position-sensitive detectors. In this paper, we report an LPE with a high self-powered position sensitivity and ultrafast optical relaxation time in S n S 2 / n - S i junctions prepared using pulsed laser deposition. A large built-in electric field was generated at the S n S 2 / S i interface, which resulted in a large LPE with a positional sensitivity of up to 116 mV/mm. Furthermore, the measurement circuit with multiple parallel resistors had a strong influence on the ultrafast optical response time of the LPE and the fastest optical relaxation time observed was ∼0.44µ s . Our results suggest that the S n S 2 / S i junction would be a promising candidate for a wide range of optoelectronic device applications.