An international team of researchers from Russia and South Korea has jointly developed a "nanoexiton transistor" that bypasses the limitations of existing transistors.
Existing transistors used to amplify, generate, switch, and convert electrical signals have an important limitation: during operation they lose some energy in the form of radiated heat, which limits the speed of signal transmission. But an international team of scientists from ITMO University (Russia) and Pohang University of Science and Technology (South Korea) managed to bypass this limitation by creating a "nanoexitonic transistor" using intra- and interlayer excitons in heterostructured semiconductors. It will allow ultra-fast signal transmission with minimal heat loss.
Excitons, responsible for the emission of light in quasiparticle semiconductors, are needed to develop next-generation light-emitting elements, which will emit less heat and become light sources for quantum information technologies. In a semiconductor two-layer heterostructure, which is a stack of two different semiconductor monolayers, there are two types of excitons: intra-layer excitons with a horizontal orientation and inter-layer excitons with a vertical orientation.
Optical signals emitted by the two types of excitons have different brightness, duration, and coherence time. This means that selective control of the two optical signals will allow the development of a two-bit exciton transistor. However, controlling intra- and interlayer excitons in nanoscale spaces has proven difficult due to the heterogeneity of semiconductor heterostructures and the low light efficiency of interlayer excitons in addition to the diffraction limit of light.
Scientists had previously proposed a technology to control excitons in nanoscale spaces, and this time, for the first time in the world, they were able to remotely control the density and luminous efficiency of excitons. The most significant advantage of this method, which combines a photonic nanoresonator and a spatial light modulator, is that it can reversibly control excitons with almost no damage to the semiconductor material. In addition, a nanoexiton transistor using "light" can help process huge amounts of data at the speed of light, minimizing thermal energy loss.
As the role of artificial intelligence increases in our lives, huge amounts of data will be needed for processing, learning and analysis, the nanoexiton transistor, the authors of the study, published in the journal ACS Nano, hope, will play an important role in future computer technology.
