Relaxation of a Stationary State on a Quantum Computer Yields Unique Spectroscopic Fingerprint of the Computer's Noise

TL;DR

This study uses relaxation dynamics of stationary states on quantum computers to generate unique spectroscopic fingerprints, revealing non-Markovian noise profiles that could inform error mitigation strategies in NISQ devices.

Contribution

It introduces a method to characterize quantum computer noise via spectroscopic fingerprints derived from relaxation simulations, highlighting non-Markovian dynamics.

Findings

Quantum computers exhibit non-Markovian noise signatures.

Spectroscopic fingerprints uniquely identify each quantum device's noise.

Results suggest potential for noise analysis to improve error mitigation.

Abstract

Quantum computing has the potential to revolutionize computing for certain classes of problems with exponential scaling, and yet this potential is accompanied by significant sensitivity to noise, requiring sophisticated error correction and mitigation strategies. Here we simulate the relaxations of stationary states at different frequencies on several quantum computers to obtain unique spectroscopic fingerprints of their noise. Response functions generated from the data reveal a clear signature of non-Markovian dynamics, demonstrating that each of the quantum computers acts as a non-Markovian bath with a unique colored noise profile. The study suggest that noisy intermediate-scale quantum computers (NISQ) provide a built-in noisy bath that can be analyzed from their simulation of closed quantum systems with the results potentially being harnessed for error mitigation or open-system simulation.