SYDNEY, July 18 (Xinhua) -- Scientists from Australia's University of New South Wales have dramatically improved on the central building blocks of quantum computing, using atoms and silicon to complete a quantum operation in 0.8 nanoseconds, 200 times faster than ever before.
Their research appeared on the cover of world-renowned journal Nature on Thursday and represents a massive breakthrough in the effort to create large-scale workable quantum computers.
Lead author Professor Michelle Simmons, director of the Centre of Excellence for Quantum Computation and Communication Technology (CQC2T), who is also the 2018 Australian of the Year, told Xinhua that the team first outlined the idea of building a quantum computer in silicon, using atoms as qubits, almost 20 years ago.
"Everyone's using different materials and every material has advantages and disadvantages," Simmons said.
"I guess the key thing about choosing atoms and silicon is that we're hoping to keep all the advantages and not have many disadvantages."
One of the challenges with creating quantum computers is how long qubits can remain in a state known as "coherence," Simmons explained.
Because atoms are so small, they don't interact with the environment as much and therefore can hold the coherence state for longer.
"The other advantages with atom qubits, if you can bring them very close together, you can get them to interact very strongly, and they should be very fast," she said.
"And so the result that we've really demonstrated today is to get to two atom qubits next to each other and show that the operation in silicon is incredibly fast."
Simmons and her team work with the atoms using a scanning probe microscope tip with which they can see the atoms directly as well as their wave functions.
"Every aspect of the device has been engineered, with sub-nanometer precision, and that is unique internationally," she said.
The team aims to produce a 10-qubit system within the next three to four years and beyond that, with help from their colleagues at CQC2T, to scale up to create a logical large scale system as well.
"The reality is, commercial application is still a decade off," Simmons said.
"And so for us at the moment, we're really understanding how the world behaves at a scale that no one else has really been able to access before - so it's a very satisfying field to be in."