Diraq, a quantum technology startup based at the University of New South Wales in Australia, has collaborated with imec, the European Microelectronics Research Center, to demonstrate that silicon-based quantum chips produced in semiconductor fabs can achieve over 99% fidelity, comparable to those produced in the laboratory. This breakthrough marks a significant step toward the practical scaling up of quantum computers. The findings are reported in the latest issue of Nature.
Silicon-based quantum computing has long been considered one of the most promising paths to large-scale applications. It allows for the integration of millions of qubits on a single chip while leveraging mature semiconductor processes. However, academia and industry had previously failed to demonstrate whether quantum chips produced in industrial settings could achieve the same high fidelity as those produced in the laboratory.
Diraq founder and CEO, Professor Andrew Dzurak of the UNSW School of Engineering, said Diraq’s chips had now been proven to be fully compatible with decades-old manufacturing engineering processes.
The research team reported in their paper that the device, designed by Diraq and manufactured by imec, achieved over 99% fidelity when performing logic operations involving two qubits. Two-bit logic gates are the fundamental building blocks of quantum computing, and their reliability is considered a key indicator for achieving large-scale fault tolerance in quantum computers.
To advance quantum computing from the laboratory to commercial applications, the US Defense Advanced Research Projects Agency (DARPA) is promoting the Quantum Benchmarking Initiative, which requires 18 companies, including Diraq, to demonstrate whether they can achieve “practical scale.” “Practical scale” means that the commercial value of a quantum computer exceeds its operating costs.
Experts believe that achieving this level requires stable manipulation of at least millions of qubits on a chip to offset the quantum state’s vulnerability to errors.
Zurak explained that this achievement demonstrates that silicon-based quantum chips can be manufactured on a large scale using existing CMOS processes, achieving high fidelity while reducing costs, and paving the way for the development of multi-million-bit quantum computers.
Previously, Diraq and imec have demonstrated that qubits fabricated using conventional semiconductor processes can achieve 99.9% fidelity when performing single-bit operations. However, to support true quantum computing capabilities, high fidelity in two-bit operations is also necessary. This breakthrough fills this critical gap.
Zurak said the latest results pave the way for the development of fully fault-tolerant, fully functional and cost-effective quantum computers.
