Note

This is the documentation for the current state of the development branch of Qiskit Experiments. The documentation or APIs here can change prior to being released.

StarkP1Spectroscopy¶

class StarkP1Spectroscopy(physical_qubits, backend=None, **experiment_options)[source]¶

P1 spectroscopy experiment with Stark tone.

Overview

This experiment measures a probability of the excitation state of the qubit with a certain delay after excitation. A Stark tone is applied during this delay to move the qubit frequency to conduct a spectroscopy of qubit relaxation quantity.

     ┌───┐┌──────────────────┐┌─┐
  q: ┤ X ├┤ Stark(stark_amp) ├┤M├
     └───┘└──────────────────┘└╥┘
c: 1/══════════════════════════╩═
                               0

Since the qubit relaxation rate may depend on the qubit frequency due to the coupling to nearby energy levels, this experiment is useful to find out lossy operation frequency that might be harmful to the gate fidelity [1].

References

[1] Malcolm Carroll, Sami Rosenblatt, Petar Jurcevic, Isaac Lauer, Abhinav Kandala, Dynamics of superconducting qubit relaxation times (open)

User manual

AC Stark Effect

Analysis class reference

qiskit_experiments.library.driven_freq_tuning.StarkP1SpectAnalysis

Experiment options

These options can be set by the set_experiment_options() method.

Options

Defined in the class StarkP1Spectroscopy:
- t1_delay (float)
  
  Default value: 2e-05
  
  The T1 delay time after excitation pulse. The delay must be sufficiently greater than the edge duration determined by the stark_sigma.
- stark_channel (PulseChannel)
  
  Default value: None
  
  Pulse channel to apply Stark tones. If not provided, the same channel with the qubit drive is used.
- stark_freq_offset (float)
  
  Default value: 80000000.0
  
  Offset of Stark tone frequency from the qubit frequency. This must be greater than zero not to apply Rabi drive.
- stark_sigma (float)
  
  Default value: 1.5e-08
  
  Gaussian sigma of the rising and falling edges of the Stark tone, in seconds.
- stark_risefall (float)
  
  Default value: 2
  
  Ratio of sigma to the duration of the rising and falling edges of the Stark tone.
- min_xval (float)
  
  Default value: -1.0
  
  Minimum x value.
- max_xval (float)
  
  Default value: 1.0
  
  Maximum x value.
- num_xvals (int)
  
  Default value: 201
  
  Number of x-values to scan.
- xval_type (str)
  
  Default value: "amplitude"
  
  Type of x-value. Either amplitude or frequency. Setting to frequency requires pre-calibration of Stark shift coefficients.
- spacing (str)
  
  Default value: "quadratic"
  
  A policy for the spacing to create an amplitude list from min_stark_amp to max_stark_amp. Either linear or quadratic must be specified.
- xvals (list[float])
  
  Default value: None
  
  The list of x-values that will be scanned in the experiment. If not set, then num_xvals parameters spaced according to the spacing policy between min_xval and max_xval are used. If xvals is set, these parameters are ignored.
- stark_coefficients (StarkCoefficients)
  
  Default value: None
  
  Calibrated Stark shift coefficients. This value is necessary when xval_type is “frequency”. When this value is None, a search for the “stark_coefficients” in the result database is run. This requires having the experiment service available in the backend set for the experiment.
Defined in the class BaseExperiment:
- max_circuits (Optional[int])
  
  Default value: None
  
  The maximum number of circuits per job when running an experiment on a backend.

Initialization

Initialize new experiment class.

Deprecated since version 0.8: The class qiskit_experiments.library.driven_freq_tuning.p1_spect.StarkP1Spectroscopy is deprecated as of qiskit-experiments 0.8. It will be removed no earlier than 3 months after the release date. Due to the deprecation of Qiskit Pulse, experiments involving pulse gate calibrations like this one have been deprecated.

Parameters:

physical_qubits (Sequence[int]) – Sequence with the index of the physical qubit.
backend (Backend | None) – Optional, the backend to run the experiment on.
experiment_options – Experiment options. See the class documentation or self._default_experiment_options for descriptions.

Attributes

analysis¶: Return the analysis instance for the experiment

backend¶: Return the backend for the experiment

experiment_options¶: Return the options for the experiment.

experiment_type¶: Return experiment type.

num_qubits¶: Return the number of qubits for the experiment.

physical_qubits¶: Return the device qubits for the experiment.

run_options¶: Return options values for the experiment run() method.

transpile_options¶: Return the transpiler options for the run() method.

Methods

circuits()[source]¶

Create circuits.

Returns:: A list of P1 circuits with a variable Stark tone amplitudes.
Return type:: list[QuantumCircuit]

config()¶

Return the config dataclass for this experiment

Return type:: ExperimentConfig

copy()¶

Return a copy of the experiment

Return type:: BaseExperiment

classmethod from_config(config)¶

Initialize an experiment from experiment config

Return type:: BaseExperiment

job_info(backend=None)¶

Get information about job distribution for the experiment on a specific backend.

Parameters:

backend (Backend) – Optional, the backend for which to get job distribution information. If not specified, the experiment must already have a set backend.

Returns:

A dictionary containing information about job distribution.

”Total number of circuits in the experiment”: Total number of circuits in the experiment.

”Maximum number of circuits per job”: Maximum number of circuits in one job based on backend and experiment settings.

”Total number of jobs”: Number of jobs needed to run this experiment on the currently set backend.

Return type:

dict

Raises:

QiskitError – if backend is not specified.

parameterized_circuits()[source]¶

Create circuits with parameters for P1 experiment with Stark shift.

Returns:: Quantum template circuit for P1 experiment.
Return type:: tuple[QuantumCircuit, …]

parameters()[source]¶

Stark tone amplitudes to use in circuits.

Returns:: The list of amplitudes to use for the different circuits based on the experiment options.
Raises:: ValueError – When invalid xval spacing is specified.
Return type:: ndarray

run(backend=None, sampler=None, analysis='default', timeout=None, backend_run=None, **run_options)¶

Run an experiment and perform analysis.

Parameters:

backend (Backend | None) – Optional, the backend to run on. Will override existing backend settings.
sampler (BaseSamplerV2 | None) – Optional, the sampler to run the experiment on. If None then a sampler will be invoked from previously set backend
analysis (BaseAnalysis | None) – Optional, a custom analysis instance to use for performing analysis. If None analysis will not be run. If "default" the experiments analysis() instance will be used if it contains one.
timeout (float | None) – Time to wait for experiment jobs to finish running before cancelling.
backend_run (bool | None) – Use backend run (temp option for testing)
run_options – backend runtime options used for circuit execution.

Returns:

The experiment data object.

Raises:

QiskitError – If experiment is run with an incompatible existing ExperimentData container.

Return type:

ExperimentData

set_experiment_options(**fields)¶

Set the experiment options.

Parameters:: fields – The fields to update the options
Raises:: AttributeError – If the field passed in is not a supported options

set_run_options(**fields)¶

Set options values for the experiment run() method.

Parameters:: fields – The fields to update the options