Algorithmic Error Mitigation Scheme for Current Quantum Processors

We present a hardware agnostic error mitigation algorithm for near term quantum processors inspired by the classical Lanczos method. This technique can reduce impact of different sources noise at sole cost an increase in number measurements to be performed on target circuit, without additional experimental overhead. demonstrate through numerical simulations and experiments IBM Quantum that proposed scheme significantly increases accuracy functions evaluations within framework variational algorithms, thus leading improved ground-state calculations chemistry physics problems beyond state-of-the-art results.