Experimentobject that can be used to calibrate the various multi-qubit observables involved in this
Experiment. This is achieved by preparing the plus-one (minus-one) eigenstate of each
out_operator, and measuring the resulting expectation value of the same
out_operator. Ideally, this would always give +1 (-1), but when symmetric readout error is present the effect is to scale the resultant expectations by some constant factor. Determining this scale factor is what we call readout calibration, and then the readout error in subsequent measurements can then be mitigated by simply dividing by the scale factor.
Returns: A new
Experimentthat can calibrate the readout error of all the observables involved in this experiment.