(Sydney.edu) Scientists and engineers at the University of Sydney and Microsoft Corporation have opened the next chapter in quantum technology with the invention of a single chip that can generate control signals for thousands of qubits, the building blocks of quantum computers.
“To realise the potential of quantum computing, machines will need to operate thousands if not millions of qubits,” said Professor David Reilly, a designer of the chip who holds a joint position with Microsoft and the University of Sydney.
“The world’s biggest quantum computers currently operate with just 50 or so qubits,” he said. “This small scale is partly because of limits to the physical architecture that control the qubits.”
“Our new chip puts an end to those limits.”
“Current machines create a beautiful array of wires to control the signals; they look like an inverted gilded birds’ nest or chandelier. They’re pretty, but fundamentally impractical. It means we can’t scale the machines up to perform useful calculations. There is a real input-output bottleneck,” said Professor Reilly, also a Chief Investigator at the ARC Centre for Engineered Quantum Systems (EQUS) .
Microsoft Senior Hardware Engineer, Dr Kushal Das, a joint inventor of the chip, said: “Our device does away with all those cables. With just two wires carrying information as input, it can generate control signals for thousands of qubits.
In order to achieve their result, the scientists at Sydney and Microsoft built the most advanced integrated circuit to operate at cryogenic temperatures.
“We have done this by engineering a system that operates in close proximity to the qubits without disturbing their operations,” Professor Reilly said.
“Current control systems for qubits are removed metres away from the action, so to speak. They exist mostly at room temperature.
“In our system we don’t have to come off the cryogenic platform. The chip is right there with the qubits. This means lower power and higher speeds. It’s a real control system for quantum technology.”