On this internship I measured physical transmon superconducting qubits devices to caracterize their decoherence through finding estimates to their T1 and T2. I also simulated the procedures of measurement to deepen my understanding of them and pinpoint the effects of each kind of fault of the system on the results of the caracterization, like noise on the qubit drive or the qubit's temperature.
You can read the partial report of the first semester here. The partial report has more details on each measurement on the physical device that I had to take out of the final report because of the size constraints. And you can also read the final report.
The TIIQx folders have the data and the notebooks used for the measurment (Measurement_pulsado.ipynb and Measurement_vna.ipynb) of each qubit sample I characterized on this internship as well as the notebook to generate the graphs for my report using this data (Qx Load_files.ipynb). The pyvisa scripts used in these notebooks to control the equipment can be found at the laboratory's github. There's also my fork with some modifications.
I also made several simulations exploring the effects of different types of noise on the qubit drive. The notebooks for the simulations are:
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Measurement procedure with collapse operators where I simulate the process of caracterizing the qubit's relaxation and dephasing gaining insights on it.
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Noisy drive decoherence effects where I pinpoint the effects of a white background noise noise on the drive of the qubit.
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Phase noise simulation where I explore the effects of noise on the phase parameter of a sine like drive signal.
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Amplitude modulated low frequency noise where I amplitude modulate (multiply) low frequency noise like pink and brownian noise with a qubit resonance drive signal carrier.
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Dephasing by noise simulation A more rigorous simulation to get a clearer picture of the effects of drive noise on dephasing (not finished).
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Qubit drift PSD simulation A study of the random walk like drift of the qubit under white noise and it's spectral characteristics.
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Coupled qubit drift PSD simulation The study above applied to a qubit coupled to another two level system (TLS).
