Physicists and engineers have found a way to identify and address imperfections in materials for one of the most promising technologies in commercial quantum computing. A University of Queensland research team has developed treatments and optimised fabrication protocols in common techniques for building superconducting circuits on silicon chips, one of the most promising technologies in commercial quantum computing.
Dr Peter Jacobson, who co-led the research, said the team had identified that imperfections introduced during fabrication reduced the effectiveness of the circuits.
"Superconducting quantum circuits are attracting interest from industry giants such as Google and IBM, but widespread application is hindered by ‘decoherence’, a phenomenon which causes information to be lost,” he said.
“Decoherence is primarily due to interactions between the superconducting circuit and the silicon chip – a physics problem – and to material imperfections introduced during fabrication – an engineering problem.
“So we needed input from physicists and engineers to find a solution.”
The team used a method called terahertz scanning near-field optical microscopy (THz SNOM) – an atomic force microscope combined with a THz light source and detector.
This provided a combination of high spatial resolution – seeing down to the size of viruses – and local spectroscopic measurements.