TY - JOUR
T1 - Spectral quantum tomography
AU - Helsen, Jonas
AU - Battistel, Francesco
AU - Terhal, Barbara M.
PY - 2019
Y1 - 2019
N2 - 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 available in the cloud, namely the QuTech Quantum Infinity and the IBM Quantum Experience. We discuss how cross-talk, leakage and non-Markovian errors affect the eigenvalue data.
AB - 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 available in the cloud, namely the QuTech Quantum Infinity and the IBM Quantum Experience. We discuss how cross-talk, leakage and non-Markovian errors affect the eigenvalue data.
UR - http://www.scopus.com/inward/record.url?scp=85071750434&partnerID=8YFLogxK
U2 - 10.1038/s41534-019-0189-0
DO - 10.1038/s41534-019-0189-0
M3 - Article
SN - 2056-6387
VL - 5
JO - NPJ Quantum Information
JF - NPJ Quantum Information
IS - 1
M1 - 74
ER -