Source code for qiskit_experiments.library.tomography.qpt_analysis
# This code is part of Qiskit.## (C) Copyright IBM 2021.## This code is licensed under the Apache License, Version 2.0. You may# obtain a copy of this license in the LICENSE.txt file in the root directory# of this source tree or at http://www.apache.org/licenses/LICENSE-2.0.## Any modifications or derivative works of this code must retain this# copyright notice, and modified files need to carry a notice indicating# that they have been altered from the originals."""Quantum process tomography analysis"""fromqiskit_experiments.frameworkimportOptionsfrom.basisimportPauliMeasurementBasis,PauliPreparationBasisfrom.tomography_analysisimportTomographyAnalysis
[docs]classProcessTomographyAnalysis(TomographyAnalysis):"""Quantum state and process tomography experiment analysis. # section: overview Fitter Functions Built-in fitter functions may be selected using the following string labels, refer to the corresponding functions documentation for additional details on the fitters. * ``"linear_inversion"``: :func:`~qiskit_experiments.library.tomography.fitters.linear_inversion` (Default) * ``"cvxpy_linear_lstsq"``: :func:`~qiskit_experiments.library.tomography.fitters.cvxpy_linear_lstsq` * ``"cvxpy_gaussian_lstsq"``: :func:`~qiskit_experiments.library.tomography.fitters.cvxpy_gaussian_lstsq` PSD Rescaling For fitters that do not constrain the reconstructed state to be `positive-semidefinite` (PSD) we construct the maximum-likelihood nearest PSD state under the assumption of Gaussian measurement noise using the rescaling method in Reference [1]. For fitters that already support PSD constraints this option can be disabled by setting ``rescale_positive=False``. # section: note Fitters starting with ``"cvxpy_*"`` require the optional CVXPY Python package to be installed. # section: warning The API for tomography fitters is still under development so may change in future releases. # section: reference .. ref_arxiv:: 1 1106.5458 """@classmethoddef_default_options(cls)->Options:"""Default analysis options Analysis Options: measurement_basis (:class:`~qiskit_experiments.library.tomography.basis.MeasurementBasis`): The measurement :class:`~qiskit_experiments.library.tomography.basis.MeasurementBasis` to use for tomographic process reconstruction. preparation_basis (:class:`~qiskit_experiments.library.tomography.basis.PreparationBasis`): The preparation :class:`~qiskit_experiments.library.tomography.basis.PreparationBasis` to use for tomographic process reconstruction. fitter (str or Callable): The fitter function to use for reconstruction. rescale_psd (bool): If True rescale the fitted state to be positive-semidefinite (Default: True). fitter_options (dict): Any addition kwarg options to be supplied to the fitter function. For documentation of available kwargs refer to the fitter function documentation. rescale_positive (bool): If True rescale the state returned by the fitter to be positive-semidefinite. See the `PSD Rescaling` section for additional information (Default: True). rescale_trace (bool): If True rescale the state returned by the fitter have either trace 1 for :class:`~qiskit.quantum_info.DensityMatrix`, or trace dim for :class:`~qiskit.quantum_info.Choi` matrices (Default: True). measurement_qubits (Sequence[int]): Optional, the physical qubits with tomographic measurements. If not specified will be set to ``[0, ..., N-1]`` for N-qubit tomographic measurements. preparation_qubits (Sequence[int]): Optional, the physical qubits with tomographic preparations. If not specified will be set to ``[0, ..., N-1]`` for N-qubit tomographic preparations. fitter (str or Callable): The fitter function to use for reconstruction. This can be a string to select one of the built-in fitters, or a callable to supply a custom fitter function. See the `Fitter Functions` section for additional information. target (str or :class:`~qiskit.quantum_info.operators.channel.quantum_channel.QuantumChannel` or :class:`~qiskit.quantum_info.Operator`): Optional, Set a custom target quantum channel for computing the :func:`~qiskit.quantum_info.process_fidelity` of the fitted process against (Default: None). conditional_circuit_clbits (list[int]): Optional, the clbit indices in the source circuit to be conditioned on when reconstructing the channel. Enabling this will return a list of reconstructed channel components conditional on the values of these clbit values. The integer value of the conditioning clbits is stored in state analysis result extra field `"conditional_circuit_outcome"`. conditional_measurement_indices (list[int]): Optional, indices of tomography measurement qubits to used for conditional state reconstruction. Enabling this will return a list of reconstructed channel components conditioned on the remaining tomographic bases conditional on the basis index, and outcome value for these measurements. The conditional measurement basis index and integer value of the measurement outcome is stored in state analysis result extra fields `"conditional_measurement_index"` and `"conditional_measurement_outcome"` respectively. conditional_preparation_indices (list[int]): Optional, indices of tomography preparation qubits to used for conditional state reconstruction. Enabling this will return a list of reconstructed channel components conditioned on the remaining tomographic bases conditional on the basis index. The conditional preparation basis index is stored in state analysis result extra fields `"conditional_preparation_index"`. """options=super()._default_options()options.measurement_basis=PauliMeasurementBasis()options.preparation_basis=PauliPreparationBasis()returnoptions