Characterization of hidden modes in networks of superconducting qubits
Abstract
We present a method for detecting electromagnetic (EM) modes that couple to a superconducting qubit in a circuit-QED architecture. Based on measurement-induced dephasing, this technique allows the measurement of modes that have a high quality factor (Q) and may be difficult to detect through standard transmission and reflection measurements at the device ports. In this scheme the qubit itself acts as a sensitive phase meter, revealing modes that couple to it through measurements of its coherence time. Such modes are indistinguishable from EM modes that do not couple to the qubit using a vector network analyzer. Moreover, this technique provides useful characterization parameters including the quality factor and the coupling strength of the unwanted resonances. We demonstrate the method for detecting both high-Q coupling resonators in planar devices as well as spurious modes produced by a 3D cavity.
Keywords
Cite
@article{arxiv.1703.04501,
title = {Characterization of hidden modes in networks of superconducting qubits},
author = {Sarah Sheldon and Martin Sandberg and Hanhee Paik and Baleegh Abdo and Jerry M. Chow and Matthias Steffen and Jay M. Gambetta},
journal= {arXiv preprint arXiv:1703.04501},
year = {2018}
}
Comments
4 pages, 2 figures; updated to published version