High-performance near-infrared photodetectors based on gate-controlled graphene–germanium Schottky junction with split active junction

The structure of a gate-controlled graphene/germanium hybrid photodetector was optimized by splitting the active region to achieve highly sensitive infrared detection capability. The strengthened internal electric field in the split active junctions enabled efficient collection of photocarriers, resulting in a responsivity of 2.02 A W−1 and a specific detectivity of 5.28 × 1010 Jones with reduced dark current and improved external quantum efficiency; these results are more than doubled compared with the responsivity of 0.85 A W−1 and detectivity of 1.69 × 1010 Jones for a single active junction device. The responsivity of the optimized structure is 1.7, 2.7, and 39 times higher than that of previously reported graphene/Ge with Al2O3 interfacial layer, gate-controlled graphene/Ge, and simple graphene/Ge heterostructure photodetectors, respectively.

Physics Based Analytical Modeling of Asymmetric Elevated Source Tunnel FET (AES-TFET) for Better Tunnel Junction Device (TJD) Performance

The authors have requested that this preprint be withdrawn due to erroneous posting.

Physics Based Analytical Modeling of Asymmetric Elevated Source Tunnel FET (AES-TFET) for Better Tunnel Junction Device (TJD) Performance

In this paper, a two-dimensional analytical model for asymmetric elevated source tunnel field effect transistor (AES-TFET) has been developed to obtain better tunnel junction device performance. Device physics based analytical modelling is performed by solving 2-D Poisson’s equation. Surface potential distribution, electric field variation and band-to-band tunneling (B2B) rate have been investigated by this numerical modelling. In our proposed structure, the source has been elevated (varied 2 nm to 6 nm) to incorporate corner effect; which boosts the carrier transport via thin tunneling barrier, with controlled ambipolar conduction. This eventually produces better source-channel interface tunneling for a n-channel AES-TFET structure. 2-D numerical device simulator (SILVACO TCAD) has been used for simulation work. The simulated graphical representations have been finally validated by analytical modelling of AES-TFET.

Photovoltaic Partner Selection for High-efficiency Photovoltaic-electrolytic Water Splitting Systems: Brief Review and Perspective

Photovoltaic-electrolysis water splitting (PV-EWS) is the most promising approach for high solar-to-hydrogen (STH) efficiency. The present PV-EWS systems achieve the highest STH performance by using a III−V triple-junction configuration, which, however, involves a complex and expensive manufacture process. Therefore, in this work, we demonstrate a III−V double junction device that can be used as an alternative to the III−V triple-junction device for high STH conversion efficiency of the PV-EWS systems. We estimate the STH performance via coupling world-recorded multi-junction photovoltaic (PV) and our experimented cell configurations with an EWS system. The results show that the III−V double junction, owing to the good trade-off between the efficiency loss and compensation, exhibits a higher STH efficiency than the III−V triple-junction. Furthermore, strategies for improving the efficiency of the III−V double junction device for low-cost PV-EWS system are discussed.

Tunable Schottky barrier height of Pt-CuO junction via triboelectric nanogenerator

Tuning Schottky barrier height is crucial to optimize the performance of Schottky junction device. Here, we demonstrate that the Schottky barrier height can be tuned by the voltage from triboelectric...