Supplemental Information: 2Q Fluxonium

Supplemental information
for cQED@20 poster

Chunyang Ding, 10 Jan 2024


Helin Zhang, Chunyang Ding, D. K. Weiss, Ziwen Huang, Yuwei Ma, Charles Guinn, Sara Sussman, Sai Pavan Chitta, Danyang Chen, Andrew A. Houck, Jens Koch, and David I. Schuster. "Tunable inductive coupler for high-fidelity gates between fluxonium qubits" arXiv 2309.05720 (2023) | (pdf link)

D. K. Weiss, Helin Zhang, Chunyang Ding, Yuwei Ma, David I. Schuster, and Jens Koch. "Fast High-Fidelity Gates for Galvanically-Coupled Fluxonium Qubits Using Strong Flux Modulation" PRX Quantum 3 040336 (2022) | (pdf link)

Leandro Stefanazzi, Kenneth Treptow, Neal Wilcer, Chris Stoughton, Collin Bradford, Sho Uemura, Silvia Zorzetti, Salvatore Montella, Gustavo Cancelo, Sara Sussman, Andrew Houck, Shefali Saxena, Horacio Arnaldi, Ankur Agrawal, Helin Zhang, Chunyang Ding, and David I. Schuster. "The QICK (Quantum Instrumentation Control Kit): Readout and control for qubits and detectors" Review of Scientific Instruments 93 044709 (2022) | (pdf link)

There have been many recent papers published demonstrating two-qubit gates using the fluxonium qubit, as follows:

In addition, our group has published two other demonstrations, in particular with heavy fluxonium qubits:

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Hamiltonian Analysis

A more detailed analysis of our Hamiltonian is found in Appendix A of the paper:

Appendix A

A full analysis of the coupled qubit Hamiltonian is given in section II.A of our theory paper, Weiss (2022). Furthermore, section IV shows a construction of the 2Q entangling gate and the results of numerical simulations of this gate on realistic qubit parameters.

Analysis of how the ZZ term is further suppressed is found in Appendix C of the paper:

Appendix C

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Error Analysis

A full error analysis is found in Appendix J of this paper. Please see below for Table 2, the summarized error budget results: Table 2

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Code Links

The QICK Github repository, from Open Quantum Hardware, used throughout this experiment: Github link here

The scqubits Github repository, as used in spectrum fitting: Github link here

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Group Photo

SLab, Winter 2022

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Download this poster!

Link to download PDF

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Hi! Thanks again for stopping by and taking a look at this poster - I really do appreciate it. Feel free to stay in touch with me (and join the WhatsApp group!), and especially reach out if you are interested in:

I feel so incredibly lucky to be meeting so many of you during this conference, and am hoping that we will be doing amazing things in the next 20 years of circuit QED.

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