A new type of transistor can dissipate almost zero heat — slashing energy usage in future quantum computers by up to 1,000 times and paving the way for massively scaled-up machines.
The engineers who created the device say it's the world's first transistor capable of functioning efficiently in cryogenic conditions — extremely low temperatures below -238 degrees Fahrenheit (-150 degrees Celsius).
It performs optimally at temperatures of 1 kelvin and lower — close to absolute zero, they explained in a study uploaded to the preprint database arXiv Oct. 1. (The study has not been peer-reviewed.)
Quantum computers need to be cooled to near-absolute zero for the qubits that power them to reach a state of "coherence," where they occupy a superposition of 1 and 0, the conventional bits of binary data. When you entangle qubits — link them over time and space so they share information — quantum computers can process calculations in parallel, whereas classical computers must process them in sequence one by one.
Conventional components perform incredibly inefficiently at these sub-freezing temperatures, the scientists said. They're also very hard to maintain — as more and more qubits are added to a system, the more heat is emitted, which makes it more difficult and expensive to sustain these ultralow temperatures.
Because the new transistor — dubbed the "cryo-CMOS transistor" — is optimized to operate at temperatures under 1 K and emit near-zero heat, it offers plenty of advantages over traditional electronics, representatives of the Finnish company SemiQon, which developed the transistor, said in a statement.
It cuts heat dissipation by 1,000 times and consumes 0.1% of the power of traditional transistors. This allows control and readout electronics to be placed directly into the "cryostat" — a gigantic barrel responsible for the cooling — for the first time. It means that future machines can be scaled up far more cost-effectively and with fewer errors that disrupt calculations.
“It was clear to us and others in the scientific community that a transistor which can operate efficiently at ultra-low temperatures would offer substantial value to users in the advanced computing sector and wherever these devices are required to function in cryogenic conditions," Himadri Majumdar, SemiQon's CEO and co-founder, said in the statement.
Beyond quantum applications, the transistors could be used in high-performance computing, like in the world's fastest supercomputers and in space, company representatives said.
