Q-CTRL is an Australian start-up that builds quantum control infrastructure software, with a focus on developing tools and techniques for error suppression. Q-CTRL’s approach applies the principles of control engineering to accelerate quantum computing technology.
This is a particular obstacle in quantum computing. While there is considerable excitement about the possibilities of quantum information and quantum computing applications – spurring billions of dollars of investment around the world – many technical hurdles have yet to be crossed. Most quantum computers are so prone to error that only the shortest, simplest algorithms can be run. When Q-CTRL experimented with algorithmic hardware systems, building on recent benchmarking experiments from the US Quantum Economic Development Consortium, the errors it encountered were initially so severe that the computers in some cases returned outputs no better than random chance.
Using speciality software to alter the building blocks of quantum algorithms (quantum logic gates), the start-up found it was able to reduce computational errors by an unprecedented degree when running algorithms on multiple IBM quantum computers.
With no changes to the test algorithm or hardware, the gate replacement alone resulted in a maximum improvement in the likelihood of quantum computing algorithm success by over 2680 per cent on real hardware. The experiments also demonstrated the new logic gates were over 400 times more efficient in preventing computational errors than any previously demonstrated techniques, considerably simplifying the procedure for a user to improve performance.
“This is the most powerful error suppression technology ever demonstrated, and delivers an enormous competitive advantage to users,” said Q-CTRL founder and CEO Professor Michael Biercuk, who is based at the University of Sydney. “These simple-to-use techniques will likely enable organisations to achieve useful quantum computing years ahead of current projections.
“We had previously demonstrated the performance of error-resilient quantum logic gates, but putting all of the pieces together and observing an algorithm run 2,500 per cent better was absolutely amazing.”
Some of the world’s largest companies – including Google, IBM, and Amazon – are racing to build the first large-scale universal quantum computer with error rates comparable to those of classical computers (approximately one million times lower than for quantum computers, at present). Earlier this year, Google reported in IEEE Spectrum the demonstration of a “stabiliser code” on its 54-qubit quantum computer which it said could reduce quantity of errors by a factor of 100.