Qubits—the building blocks of quantum computing—are driving advancements across the tech industry. Among them, superconducting qubits hold great promise for large-scale quantum computers. However, they rely on electrical signals, making them challenging to scale.

In a breakthrough, physicists at the Institute of Science and Technology Austria (ISTA) have successfully developed a fully optical readout for superconducting qubits, overcoming a key technological hurdle. Their findings, recently published in Nature Physics.

<em>Nature Physics</em> is a prestigious, peer-reviewed scientific journal that publishes high-quality research across all areas of physics. Launched in 2005, it is part of the Nature family of journals, known for their significant impact on the scientific community. The journal covers a wide range of topics, including fundamental physics, applied physics, and interdisciplinary research that bridges physics with other scientific disciplines. Nature Physics aims to highlight the most impactful and cutting-edge research in the field, providing insights into theoretical, experimental, and applied physics. The journal also features reviews, news, and commentary on major advances and issues affecting the physics community.

Hundreds of quantum computing firms around the world are racing to commercialise these once-exotic devices, but the jury is still out on who is going to pull ahead and produce a machine that actually does something useful.

By Karmela Padavic-Callaghan

Qubits—the fundamental units of quantum information—drive entire tech sectors. Among them, superconducting qubits could be instrumental in building a large-scale quantum computer, but they rely on electrical signals and are difficult to scale.

In a breakthrough, a team of physicists at the Institute of Science and Technology Austria (ISTA) has achieved a fully optical readout of superconducting qubits, pushing the technology beyond its current limitations. Their findings are published in Nature Physics.

Following a year-long rally, quantum computing stocks were brought to a standstill barely a few days into the International Year of Quantum Science and Technology. The reason for this sudden setback was Nvidia CEO Jensen Huang’s keynote at the CES 2025 tech trade show, where he predicted that “very useful quantum computers” were still two decades down the road.

This hybrid system allows precise manipulation of quantum states while naturally modeling real-world physics, enabling breakthroughs in fields like magnetism, superconductors, and even astrophysics.

Breakthrough in Quantum Simulation

Physicists working in Google’s laboratory have developed a new type of digital-analog quantum simulator, capable of studying complex physical processes with unprecedented precision and adaptability. Two researchers from PSI’s Center for Scientific Computing, Theory, and Data played a crucial role in this breakthrough.

Exotic superconducting states could exist in a wider range of materials than previously thought, according to a theoretical study by two RIKEN researchers published in Physical Review B.

Superconductors conduct electricity without any resistance when cooled below a critical temperature that is specific to the superconducting material. They are broadly classified into two types: conventional superconductors whose superconducting mechanism is well understood, and unconventional superconductors whose mechanism has yet to be fully determined.

Superconductors have intrigued scientists since their first experimental demonstration at the beginning of the 20th century. This is not just because they have numerous applications, including great promise for quantum computing, but also because superconductors host a rich range of fundamental physics that has allowed physicists to gain a deeper understanding of material science.