A collaborative study by QphoX, Rigetti Computing, and Qblox, published in Nature Physics, demonstrates the successful optical readout of superconducting qubits using a microwave-to-optical transducer. This breakthrough addresses a critical scalability challenge in quantum computing by replacing bulky coaxial cables with compact, low-heat optical fibers, enabling the operation of large-scale quantum processors.
Superconducting qubits, a leading quantum computing platform, require cryogenic environments and extensive microwave wiring, which limits scalability. QphoX’s piezo-optomechanical transducer converts microwave signals from qubits into infrared light, transmitted via optical fibers with minimal thermal load. The study confirmed that the transducer can accurately measure qubit states while protecting them from decoherence caused by thermal noise or stray photons. In the study, the team achieved a single-shot readout fidelity of 81% using a demolition readout technique. The team indicates they are continuing their development efforts on this technology and expect to achieve significant improvements and obtain groundbreaking performance in the coming years.
“This demonstration shows that optical transducers are ready to interface with superconducting qubits, paving the way for scalable quantum computing,” said Dr. Thierry van Thiel, lead author and Quantum Engineer at QphoX. The collaboration highlights the potential of optical readout to support fault-tolerant quantum systems with millions of qubits.
For more information, read the full study here, QphoX’s blog post here, and Rigetti Computing’s press release here.
February 13, 2025
