Quantum process tomography of a compressed time evolution circuit on superconducting quantum processors

Abstract: As present day quantum hardware is limited by various noise mechanisms, quantum advantage can only be reached in the near-term by designing noise-resilient quantum algorithms. In this work, we employ state-of-the-art quantum process tomography (QPT) techniques to characterize the noise channels of IBM quantum processors under realistic runtime constraints. As our main application, we compare the Trotter time-evolution of three- and four-qubit wave functions to a compressed quantum circuit version of the same evolution operator. By analysing the spectral properties of the two process channels, we find that the compressed circuit systematically yields larger eigenvalue moduli, demonstrating better noise resilience.