CQEDToolbox

The Pfafflab's circuit QED measurement workflows, open-sourced.

CQEDToolbox implements lab-specific measurement protocols, instrument drivers, and analysis routines on top of labcore and QCodes. labcore provides the building blocks (sweep framework, data storage, fitting tools); CQEDToolbox is how we wire them together to run real experiments. You're welcome to use it as-is or as a starting point for your own lab's workflow.

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What's inside

Measurement protocols

Ready-to-run experiments for single-qubit characterization, organized by qubit type:

Transmon

• Resonator spectroscopy (bare and dispersive, vs. readout gain)
• Qubit spectroscopy (saturation, π-pulse)
• T1, T2 Ramsey, T2 Echo
• Power Rabi
• Readout calibration
• Single-qubit tuneup sequences: AllXY, Pauli bars, pulse trains, interleaved randomized benchmarking (IRB)

Fluxonium

• Resonator spectroscopy vs. flux
• Qubit spectroscopy, power Rabi

Control electronics

• OPX (Quantum Machines) — config generation, mixer calibration, sweep integration
• QICK (Xilinx RFSoC) — config and sweep support

QCodes instrument drivers

Instrument	Driver
SignalCore SC5511A / SC5521A	RF signal generators
Oxford Instruments Triton	Dilution refrigerator
Yokogawa GS200	DC voltage/current source
Keysight N9030B / P937A	Spectrum analyzer / VNA
SignalHound Spike	Spectrum analyzer
ThorLabs TSP-01B	Temperature/humidity sensor

Fit functions

Resonator fit models built on top of labcore's lmfit-based fitting framework.

Readout analysis

Qubit readout discrimination and calibration utilities.

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Installation

CQEDToolbox is not yet on PyPI. Install directly from GitHub:

pip install git+https://github.com/toolsforexperiments/CQEDToolbox.git

Or clone and install in editable mode:

git clone https://github.com/toolsforexperiments/CQEDToolbox.git
pip install -e CQEDToolbox/

Note: Some dependencies (qick, qm-qua) require hardware-specific installations and may not resolve cleanly on all platforms. See the dependency notes in pyproject.toml.

Requires Python ≥ 3.11.

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Relationship to labcore

CQEDToolbox depends on labcore, which provides:

• The sweep framework (Sweep, sweep_parameter, @recording)
• HDF5 data storage (DDH5Writer, load_as_xr)
• The base fitting and analysis infrastructure

If you are not from a CQED lab, labcore alone may be all you need. CQEDToolbox adds the physics-specific layer on top.

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Development

git clone https://github.com/toolsforexperiments/CQEDToolbox.git
cd CQEDToolbox
pip install -e ".[dev]"
pytest

Code quality:

ruff check --fix .
ruff format .
mypy .

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License

MIT. See LICENSE for details.