Data and code for "Quasiparticle effects in magnetic-field-resilient 3D transmons"

This folder contains all data files and Jupyter notebooks needed to recreate the figures of our publication, "Quasiparticle effects in magnetic-field-resilient 3D transmons",written by J. Krause, G. Marchegiani, L. M. Janssen, G. Catelani, Yoichi Ando, and C. Dickel

Measurements were done with quantify-core (https://quantify-os.org/docs/quantify-core/)

Required python packages are quantify-core (tested to run with version 0.7.4) and all its dependencies, as well as cmcrameri (colormaps used for plots).Qutip is used for master equation solving and Hamiltonian modeling (used version 4.7.5) and hmmlearn (version 0.3.2) for fitting gaussian hidden-markov-models.From a clean conda environment one should just install the above 4 packages and it should work.

Content:Data/ Contains the plotted measurement data used in the figures of the paper mostly in csv format.The datasets are loaded and plotted in the respective notebooks for all figures. 

Data/quantify_datasets/Contains a few quantify datasets (raw data format of quantify measurements)

Data/20220710_parity_paper_device_afm/Contains .tiff images and .txt files with AFM data of the device

Figures/Contains all paper figures as .pdf files

Fits/transmon_spectrum_including_EJ_harmonicsContains some auxiliary fit results so the fits of flux arcs do not have to be repeated.

Fits/Gap_vs_BparContains numerical results for the superconducting gap Delta as a function of magnetic field for aluminum films of different thickness.Used to check the cavity data and not used for other modeling.Imported in Jupyter_notebooks/models_transmon_spectrum_including_higher_harmonics.py

Jupyter_notebooks/Contains the jupyter notebooks with the code that creates the figures including the relevant calculations and fits and the loading of the data.The notebook name gives the figure(s) it creates.There are several auxiliary .py files and two notebooks that do not make paper figures:

Jupyter_notebooks/fit_params.pyContains the fit parameters for the quasiparticle modeling and the transmon spectrum

Jupyter_notebooks/models_qp_dynamics.pyContains the functions for quasiparticle modeling vs field and temperature.

Jupyter_notebooks/models_transmon_spectrum_including_higher_harmonics.pyContains the models for the field dependent spectrum

Jupyter_notebooks/models_cavity_transmon_interaction.pyContains qutip model for the fitting of the transmon-cavity Hamiltonian to estimate the bare-dressed changes.

Jupyter_notebooks/fit_quasiparticle_model.ipynbNotebook that shows how the quasiparticle model can be fit to the dataTakes a bit longer to execute

Jupyter_notebooks/fit_cavity_transmon_interaction.ipynbLooks at a resonator-transmon model to understand the bare-dressed difference and estimate the coupling.Not really used in the paper, except to estimate G.