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The van der Waals heterojunction based on transition metal dichalcogenides has broad research value and application prospects as the basic material for advanced near‐infrared polarized photodetectors. a type II heterojunction based on the 2H‐MoTe2/1T′‐MoTe2/MoSe2 structure is reported for photovoltaic photodetectors. Notably, this device generates a self‐powered photocurrent, eliminating the need for an external bias or gate voltage. This device has the ability to detect polarized light, and its photocurrent anisotropy ratio is 55. The device performance is significantly amplified due to the proficient facilitation of electron‐hole separation through the type II band structure of MoSe2 at the bottom and 2H‐MoTe2 at the top, as well as enhanced exciton splitting by 1T′‐MoTe2 situated in the middle. Consequently, the device demonstrates exceptional proficiency, presenting a noteworthy response rate of 0.76 A W−1, a high detection rate of 3 × 109 Jones, an elevated EQE of 71%, and rapid rising and falling response speeds of 13 ms/10 ms respectively. Moreover, the device's anisotropy ratio of photocurrent highlights its sensitivity to polarized light, making it a promising candidate for applications in polarized photodetection. Overall, this innovative heterostructure opens new avenues for exploring and developing advanced optoelectronic devices based on 2D van der Waals materials. [ABSTRACT FROM AUTHOR]

Autologous fat transplantation in the treatment of velopharyngeal insufficiency has the advantages of good histocompatibility, small local trauma, few complications, reversible operation and simple postoperative nursing, which can effectively increase the velopharyngeal closure area. If the clinical effect is poor, other surgical methods can be used at any time for replacement. Although there are many advantages in the treatment of velopharyngeal insufficiency with autologous fat transplantation, there are still some problems in the selection of indication, donor site, injection dose, recipient site, follow-up evaluation, complications and prevention and treatment. Current research shows that autologous fat transplantation is mainly used in patients with mild or moderate velopharyngeal insufficiency, but with the improvement of fat acquisition and treatment techniques, the indications for autologous fat transplantation continue to expand, and autologous fat transplantation combined with palatoplasty or pharyngoplasty has been proposed for the treatment of severe velopharyngeal insufficiency. However, there are complications, such as fat absorption and obstructive sleep apnea syndrome. In addition, the application of autologous fat transplantation in severe VPI patients and how to improve the long-term stability of autologous fat transplantation need further study.

InAs/AlSb is a material system that can be used as a low-noise avalanche detector and operates in the short-wave infrared band. The interface parameters determine the wave function overlap (WFO). Maximizing the WFO of InAs/AlSb superlattices improves the quantum efficiency (QE) of infrared avalanche photodetectors (APDs). However, this remains a huge challenge. Here, the 8-band k·p perturbation method based on Bloch wave envelope function approximation was used to calculate the energy level structure of InAs/AlSb superlattices. The results indicate that the WFO is enhanced with increasing InSb interface thickness or when the InSb (or AlAs) interface is far from the intersection of InAs and AlSb. As the AlAs interface thickness increases, the WFO enhances and then reduces. The maximum increase in WFO is 15.7%, 93%, and 156.8%, respectively, with three different models. Based on the stress equilibrium condition, we consider the interface engineering scheme proposed for enhancing WFO with an increase of 16%, 114%, and 159.5%, respectively. Moreover, the absorption wavelength shift is less than ±0.1 μm. Therefore, the interface layer thickness and position can be designed to enhance the WFO without sacrificing other properties, thereby improving the QE of the device. It provides a new idea for the material epitaxy of APDs. [ABSTRACT FROM AUTHOR]