Error Filtration for Quantum Computation

Efficient suppression of errors without error correction is crucial for applications with NISQ devices. Error mitigation allows us to suppress errors in measuring expectation values without the need for any error correction code, but its applications are limited because it does not provide us with high-fidelity quantum operations acting on arbitrary quantum states. To address this challenge, we propose to use error filtration (EF) for gate-based quantum computation, as a practical error suppression scheme without resorting to full quantum error correction. We further analyze the application of EF to quantum random access memory, where EF offers a hardware-efficient error suppression scheme.