The world's first microwave Photodetector Based on

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World first! Microwave photodetectors based on graphene devices

graphene has little use in the field of digital electronics due to its lack of inherent energy gap. However, in the field of optoelectronics, graphene, which has no gap, seems to be attracting the attention of many researchers. This feature is particularly prominent in the field of photodetectors. Graphene makes more efficient near terahertz photodetectors possible. Recently, researchers from Daegu gyeongbei Institute of Technology (dgist) in South Korea and the University of Basel in Switzerland developed a new graphene photodetector that can work at microwave wavelengths. This is quite different from graphene photodetectors that can only detect the wavelength range from near-infrared light to ultraviolet light, which can be seen in the light wavelength range

"the significance of this research is that we have developed the world's first microwave Photodetector Based on graphene devices," said Jung min Kyung, a senior researcher at dgist in a draft

the device can detect light energy with the detection energy level of the existing graphene photodetector being 100000 times smaller

in this article published in nano letter, the research team studied the microwave absorption capacity of double-layer graphene arranged in PN junction, which is the node formed by connecting p-type and n-type semiconductors. It is the basis of many familiar electronic devices

of course, many researchers have made many researches and attempts on photoelectric detection in the microwave range, but these attempts have failed because the microwave on the detector itself has much smaller energy than the surface potential difference caused by the surrounding environment. The reasons for the failure include the residues left on the surface of graphene during manufacturing

in order to overcome this problem, researchers have found another way. They made a bridge structure that suspended the p-n junction above the substrate, so that the graphene based p-n junction was separated from the substrate. This bridge structure essentially allows electrons to flow freely without colliding with obstacles caused by residues on the device

researchers can detect photocurrent by measuring the temperature difference between electrodes, so as to confirm that they have indeed made microwave photodetectors. Basically, with the increasing number of electron hole pairs generated in graphene p-n junctions, the demand for new non-ferrous metal materials including silicon, cobalt, lithium, indium, bismuth, germanium, gallium, selenium, tellurium, zirconium, chromium and so on is increasing, and the junction temperature is increasing

researchers seem to be considering using this microwave photodetector for wearable devices and flexible displays. Zheng Minyu added: "By developing new application devices, such as the large-area microwave photodetector of graphene, which is an innovative, open and practical R & D platform for the innovative development of aluminum based new technologies, the transformation of achievements, the construction and cultivation of scientific and technological talent team based on efforts to build the innovation center into a domestic leading level, we will further study it to improve the performance of wearable devices and flexible displays."

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