Researchers at the University of Hong Kong (HKU) have announced significant advances in cryogenic electronics that could overcome key challenges in quantum computing and support future deep space missions. A team from the University of Hong Kong’s School of Electrical and Computer Engineering and Center for Advanced Semiconductors and Integrated Circuits (CASIC) has developed a programmable neuromorphic hardware platform that can operate at temperatures close to absolute zero.
The research was led by Professor Yuhao Zhang and PhD student Xin Yang. Their research introduced a new method to generate and control negative differential resistance (NDR) in industry-standard silicon carbide (SiC) MOSFETs. Using this approach, the researchers demonstrated for the first time that a single transistor can reproduce the energy-efficient “spiking” activity of biological neurons at temperatures as low as 10 mK.
Brain-inspired quantum computing hardware
Quantum computers rely on sophisticated control electronics to manage the qubits. Qubits are very sensitive and must be kept at milli-Kelvin temperatures. Existing silicon-based control systems consume significant power and generate unnecessary heat, so they must be located away from the qubits themselves. This distance creates extensive wiring requirements that can hinder performance and make building large-scale quantum computers more difficult.
“Our research introduces a hardware platform that can be integrated with quantum processors,” Professor Zhang said. “By exploiting silicon carbide’s unique carrier dynamics, we can create circuits that are thousands of times more energy efficient than traditional electronics, significantly reducing the thermal load in cryogenic systems.”
Silicon carbide reveals unique cryogenic behavior
The research team found that SiC MOSFETs exhibit a strong “S-shaped” NDR effect when cooled below 2K. This behavior is caused by electron donor impact ionization (EDII). Unlike other techniques that rely on heat generated within the device, the newly observed mechanism arises directly from the atomic properties of the material. As a result, it is highly stable and consistently reproducible between different manufacturing batches.
“This is a robust and scalable approach,” Yang said. “SiC is already used around the world in electric vehicles and power grids, so we can leverage existing industrial foundries to manufacture cryogenic chips on 300 mm wafers.”
From artificial neurons to deep space missions
The study also demonstrated that these artificial neurons can be linked together, or “cascaded” into larger networks. This capability enables advanced local data processing at cryogenic temperatures, potentially improving important quantum computing capabilities such as quantum error correction and real-time quantum control.
The potential applications go far beyond quantum computing. The circuit is designed to work reliably in extremely cold environments, so it could also be useful for deep space exploration. Future systems may be able to function in the harsh conditions found on the surface of the moon and in distant regions of the solar system.
The survey results are nature communications In a paper titled “Cryogenic neuromorphic circuit using gated negative differential resistance in silicon carbide”.
