Two-dimensional materials (2DMs) have been used widely in constructing photodetectors (PDs) because of their advantages in flexible integration and ultrabroad operation wavelength range. Specifically, 2DM PDs on silicon have attracted much attention because silicon microelectronics and silicon photonics have been developed successfully for many applications. 2DM PDs meet the imperious demand of silicon photonics on low-cost, high-performance, and broadband photodetection. In this work, a review is given for the recent progresses of Si/2DM PDs working in the wavelength band from near-infrared to mid-infrared, which are attractive for many applications. The operation mechanisms and the device configurations are summarized in the first part. The waveguide-integrated PDs and the surface-illuminated PDs are then reviewed in details, respectively. The discussion and outlook for 2DM PDs on silicon are finally given.

Organic semiconductors have attracted tremendous attention in the past few years, thanks to their excellent flexibility, solution-processability, low-cost, chemical versatility, etc. Particularly, organic solar cells based on ternary heterojunctions have shown remarkable device performance, with the recent development of nonfullerene acceptor materials. These novel materials are also promising for photodetection. However, there are several key limits facing organic photodetectors, such as relatively large bandgaps, poor charge transport, and stability. In this work, a novel nonfullerene acceptor-CO i 8DFIC-is introduced, blended with a fullerene derivative and a donor to form ternary heterojunctions. After optimization, photodiodes based on such ternary blends exhibit compelling performance metrics, including low dark current, decent responsivity, large linear dynamic range, fast response, and excellent stability. This device performance is actually on a par with the established silicon technology, suggesting great potential for photodetection and imaging.

Accurate classification of Alzheimer’s Disease (AD) and its prodromal stage, Mild Cognitive Impairment (MCI), plays a critical role in possibly preventing progression of memory impairment and improving quality of life for AD patients. Among many research tasks, it is of particular interest to identify noninvasive imaging biomarkers for AD diagnosis. In this paper, we present a robust deep learning system to identify different progression stages of AD patients based on MRI and PET scans. We utilized the dropout technique to improve classical deep learning by preventing its weight co-adaptation, which is a typical cause of over-fitting in deep learning. In addition, we incorporated stability selection, an adaptive learning factor, and a multi-task learning strategy into the deep learning framework. We applied the proposed method to the ADNI data set and conducted experiments for AD and MCI conversion diagnosis. Experimental results showed that the dropout technique is very effective in AD diagnosis, improving the classification accuracies by 5.9% on average as compared to the classical deep learning methods.

Hierarchical CoMoO4 porous micro-flowers assembled from numerous ultrathin nanosheets were synthesized by a facile hydrothermal method. Benefiting from the high specific surface area and constituent nanosheets with an ultrathin thickness, the CoMoO4 micro-flowers exhibit substantially higher electrocatalytic activity and stability than the IrO2 benchmark for the oxygen evolution reaction.

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With the rapid development of electronic and computing technology, multi-view video is attracting extensive interest recently due to its greatly enhanced viewing experience. In this paper, we present the system architecture for real-time capturing, processing, and interactive delivery of multi-view video. Unlike previous systems that mainly focus on multiview video capturing, our system is designed to provide multi-view video service with high degree of interactivity in real time, which is still challenging in the current state of the technology. The proposed architecture tackles many practical problems in system calibration, object tracking, video compression, interactive delivery, etc. With the proposed system, users can interactively select their desired viewing directions and enjoy many exciting visual experiences, such as view switching, frozen moment and view sweeping, in real-time and with great freedom.

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