State Purification with Symmetry Subgroup Projectors

Learn about quantum state purification through this conference talk that introduces an innovative purification gadget using symmetry subgroup projectors. Explore how this method achieves inverse-linear performance scaling relative to the number of state copies at a fixed stochastic error rate, significantly reducing implementation overhead compared to previous approaches. Discover the practical applications of this technique in designing robust verification protocols for quantum outputs in pre-fault-tolerant quantum computing environments. Presented at the 19th Conference on the Theory of Quantum Computation, Communication and Cryptography (TQC 2024) by Bo Yang, Elham Kashefi, Dominik Leichtle, and Harold Ollivier, this research addresses the critical need for effective quantum state purification in near- and middle-term quantum ecosystems.