Quantum Elements and USC have published a peer-reviewed Quantum Monte Carlo algorithm in Physical Review Letters that enables more efficient classical simulation of noisy quantum circuits. The algorithm compresses noisy quantum-circuit simulations while preserving dynamics relevant to quantum error correction, correlated noise, and decoder performance. In a collaboration with AWS and Harvard, the method was used to simulate a 97-physical-qubit, distance-7 surface-code syndrome-extraction round on classical HPC infrastructure in about an hour on a single compute node — a task that would otherwise require tracking 4^97 density-matrix entries with brute-force methods. The work supports Quantum Elements' development of quantum error-correction digital twins and provides a rigorous foundation for hardware-software feedback loops needed for fault-tolerant quantum computing.
