Researchers from the Universitat Autònoma de Barcelona (UAB) have played a key role in the development of an innovative switch that promises to revolutionize telecommunications. This new switch operates at exceptionally high frequencies while consuming significantly less power than current technologies, making it ideal for next-generation 6G mass communication systems. The findings of this groundbreaking study were recently published in the journal Nature Electronics.
Switches are essential components in electronic communication devices, as they control signals by either allowing an electrical signal to pass (ON state) or blocking it (OFF state). Currently, the fastest switches used are silicon-based, specifically RF silicon-on-insulator MOSFET switches, which operate at frequencies of tens of gigahertz (GHz). However, these switches are volatile and require a constant power source to maintain their ON state. As the demand for faster communications grows, particularly with the rise of the Internet of Things (IoT) and the popularization of virtual reality, there is a pressing need to develop switches that can operate at higher frequencies and with better performance.
In response to this need, an international collaboration involving researchers from the UAB Department of Telecommunications and Systems Engineering has developed a switch capable of performing at twice the operating frequency of current silicon-based devices, reaching up to 120 GHz, without needing a constant voltage. This advancement marks a significant leap forward in switch technology.
The new switch utilizes a non-volatile material known as hexagonal boron nitride (hBN), which allows the switch’s ON or OFF state to be controlled by applying an electrical voltage pulse rather than a continuous signal. This feature leads to substantial energy savings, making the switch much more sustainable.
“Our research team from the Department of Telecommunications and Systems Engineering at the UAB was involved in the design of the devices and their experimental characterization in the laboratory,” explained Jordi Verdú, a researcher at UAB. “For the first time, we have demonstrated the operation of a switch based on hBN, a non-volatile material, in a frequency range of up to 120 GHz. This suggests the possibility of using this technology in the new 6G mass communications systems, where a very high number of these elements will be required.” Verdú emphasized the importance of this development, noting its significance not only in terms of device performance but also in promoting a much more energy-efficient technology.
The operation of these devices is based on the property of memristance, which is the change in electrical resistance of a material when a voltage is applied. Previously, very fast switches had been experimentally developed from memristors created with two-dimensional networks of hBN. These devices could reach frequencies up to 480 GHz but were only stable for about 30 cycles, limiting their practical application. The new switch improves upon this by using a superposition of layers of hBN (between 12 and 18 layers), achieving stable operation at 260 GHz for approximately 2000 cycles, making it viable for electronic devices.
This research, coordinated by the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia, included contributions from UAB researchers Jordi Verdú, Eloi Guerrero, Lluís Acosta, and Pedro de Paco, along with collaborators from the University of Texas at Austin (USA), the Tyndall National Institute, and University College Cork (Ireland).