Researchers at the University of Michigan have developed an electronic “invisible ink” that can help alert users to any unauthorized device tampering. < / P > < p > it is understood that the device consists of a tungsten dichloride semiconductor layer only three atoms thick, above the azobenzene molecular layer. When azobenzene is exposed to ultraviolet light, it contracts and stretches the tungsten dichloride atom above it. In turn, they change the wavelength of the light they emit. < / P > < p > in fact, this means that users can write information or draw symbols on azobenzene with ultraviolet light, and when light of a certain wavelength is illuminated on the surface of tungsten selenide, the same shape of light will appear on the surface. If azobenzene is exposed to visible light, it will relax again and completely erase the information. < / P > < p > the team that developed the technology said their idea was that if the chip was tampered with, the fraudster would inadvertently erase the trademark when opening the box. By checking the symbols, users can easily detect this tampering behavior. “It’s hard to detect if the device has been tampered with,” says Parag deotare, a corresponding author of the study. While it may work well, it may do more than it should, sending information to third parties. ” However, the memory can only be stored in the dark for a week. In addition, a blue light will erase the past when necessary and be ready to rewrite it. < / P > < p > the team says their next step is to find ways to extend the time the material can hold information, so that it can play a role in anti-counterfeiting. [image] Google secretly tests 6GHz networks in 17 states of the United States