# Spectral quantum tomography

@article{Helsen2019SpectralQT,
title={Spectral quantum tomography},
author={J. Helsen and F. Battistel and B. Terhal},
journal={npj Quantum Information},
year={2019},
volume={5},
pages={1-11}
}
• Published 2019
• Physics
• npj Quantum Information
We introduce spectral quantum tomography, a simple method to extract the eigenvalues of a noisy few-qubit gate, represented by a trace-preserving superoperator, in a SPAM-resistant fashion, using low resources in terms of gate sequence length. The eigenvalues provide detailed gate information, supplementary to known gate-quality measures such as the gate fidelity, and can be used as a gate diagnostic tool. We apply our method to one- and two-qubit gates on two different superconducting systems… Expand

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