Quantum computers could revolutionize the electronics industry, offering processing speeds many times faster than today's technology, but the designs suffer from a serious drawback: overheating. Now, researchers from the University of Utah believe they have developed a new way to operate the theoretical systems without high temperatures becoming an issue.
A silicon semiconductor was covered in a thin layer of metal, in a form of "topological insulator." This hybrid sheet is able to conduct electricity along its outer shell, while the inside retains properties as an insulator.
Topological insulators were first developed near the beginning of the 21st century, and immediately attracted interest as a potential technology for quantum computing. Since that time, researchers have worked to develop such a system capable of maintaining a large energy gap. This is the amount of energy needed for electrons to transport electricity across the surface of a given material. If the gap is large enough, a processor could function at room temperatures.
Bismuth was coupled with silicon in this latest technology, allowing the materials to be physically bonded to each other, while remaining separated electronically. This pairing could prove to be both functional and economical.
"We can put it on silicon so it can be married or combined with the existing semiconductor technology. This is very important. It makes it more experimentally feasible and practically realistic," Feng Liu, materials science and engineering professor at the University of Utah, said.
This combination was found to exhibit the greatest energy gap ever predicted, and could make room-temperature devices, including quantum computers, possible.
Quantum computers have not yet been constructed, but the theory behind them employs the unique properties of subatomic particles to exist in more than one state, or condition, at once. Processors built using such technology could be billions of times faster than modern supercomputers. Once developed, these super-fast computers would likely find use right away for military purposes, as well as weather prediction and code breaking.
A topological insulator like the one developed at the University of Utah could be employed in the development of new spintronic devices, in addition to quantum computing. This is a new field of electronics that operates using the "spin" of sub-atomic particles. Despite the confusing name, this property of particles does not represent any physical spin of the tiny building blocks of matter. This is a measure of how the particle affects what is immediately around it, like a spinning magnet.
Development of the bismuth-silicon topological insulator was profiled in the journal Proceedings of the National Academy of Sciences.