Optical switch protocol verifies entangled quantum states in real time without destroying them

University of Vienna researchers developed an optical switch protocol that verifies entangled quantum states in real time without full destruction, addressing a longstanding challenge in quantum measurement. The method enables efficient quantum state certification, preserving some states for further use—a critical advancement for scalable quantum computing and network development. Traditional quantum measurement destroys systems upon observation, but this protocol minimizes loss by avoiding complete state collapse, offering a practical solution for fragile quantum systems. Published in February 2026, the breakthrough reduces time-consuming characterization processes, accelerating quantum technology deployment in communications and computation. This non-destructive verification could enhance error correction and reliability in quantum networks, marking a pivotal step toward robust, large-scale quantum infrastructure.