Example Q6: Calibrations

This example notebook shows how to use the pulse calibration framework.

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from QGL import *
from auspex.qubit import *

We use a pre-existing database containing a channel library and pipeline we have established.

cl = ChannelLibrary("my_config")
pl = PipelineManager()

Calibrating Mixers

The APS2 requires mixers to upconvert to qubit and cavity frequencies. We must tune the offset of these mixers and the amplitude factors of the quadrature channels to ensure the best possible results. We repeat the definition of the spectrum analyzer here, assuming that the LO driving this instrument is present in the channel library as spec_an_LO.

spec_an = cl.new_spectrum_analzyer("SpecAn", "ASRL/dev/ttyACM0::INSTR", cl["spec_an_LO"])
cal = MixerCalibration(q2, spec_an, mixer="measure")
cal.calibrate()

If the plot server and client are open, then the data will be plotted along with fits from the calibration procedure. The calibration procedure automatically knows which digitizer and AWG units are needed in the process. The relevant instrument parameters are updated but not commited to the database. Therefore they may be rolled back if undesirable results are found.

Pulse Calibrations

A simple set of calibrations is performed as follows.

cals = RabiAmpCalibration(q2)
cal.calibrate()

cal = RamseyCalibration(q2)
cal.calibrate()

Of course this is somewhat repetetive and can be sped up:

cals = [RabiAmpCalibration, RamseyCalibration, Pi2Calibration, PiCalibration]
[cal(q2).calibrate() for cal in cals]

Automatic Tuneup

While we develop algorithms for fully automated tuneup, some segments of the analysis are (primitively) automated as seen below:

cal = QubitTuneup(q2, f_start=5.2e9, f_stop=5.8e9, coarse_step=50e6, fine_step=0.5e6, averages=250, amp=0.1)
cal.calibrate()