laboneq_applications.experiments.lifetime_measurement

This module defines the lifetime_measurement experiment.

In this experiment, the qubit is first excited to either its first or a higher excited state and then allowed to relax back to the ground state over a variable delay period, enabling us to measure the qubit's longitudinal relaxation time, lifetime_measurement, for the respective state.

The lifetime_measurement experiment has the following pulse sequence:

qb --- [ prep transition ] --- [ x180_transition ] --- [delay] --- [ measure ]

If multiple qubits are passed to the run workflow, the above pulses are applied in parallel on all the qubits.

create_experiment(qpu, qubits, delays, options=None)

Creates a lifetime_measurement Experiment.

Parameters:

Name	Type	Description	Default
qpu	QPU	The qpu consisting of the original qubits and quantum operations.	required
qubits	QuantumElements	The qubits to run the experiments on. May be either a single qubit or a list of qubits.	required
delays	QubitSweepPoints	The delays to sweep over for each qubit. If qubits is a single qubit, amplitudes must be a list of numbers or an array. Otherwise it must be a list of lists of numbers or arrays.	required
options	TuneupExperimentOptions | None	The options for building the experiment. See [TuneupExperimentOptions] and [BaseExperimentOptions] for accepted options. Overwrites the options from [TuneupExperimentOptions] and [BaseExperimentOptions].	None

Returns:

Name	Type	Description
experiment	Experiment	The generated LabOne Q experiment instance to be compiled and executed.

Raises:

Type	Description
ValueError	If the qubits and qubit_delays are not of the same length.
ValueError	If qubit_delays is not a list of numbers when a single qubit is passed.
ValueError	If qubit_delays is not a list of lists of numbers.
ValueError	If the experiment uses calibration traces and the averaging mode is sequential.

Example

options = {
    "count": 10,
    "transition": "ge",
    "averaging_mode": "cyclic",
    "acquisition_type": "integration_trigger",
    "cal_traces": True,
}
options = TuneupExperimentOptions(**options)
setup = DeviceSetup("my_device")
qpu = QPU(
    quantum_elements=[TunableTransmonQubit("q0"), TunableTransmonQubit("q1")],
    quantum_operations=TunableTransmonOperations(),
)
temp_qubits = qpu.copy_quantum_elements()
create_experiment(
    qpu=qpu,
    qubits=temp_qubits,
    delays=[[10e-9, 50e-9, 1], [10e-9, 50e-9, 1]],
    options=options,
)

evaluate_experiment(analysis_results, qubits, evaluation_parameters=None)

Evaluates the lifetime measurement analysis workflow result.

Parameters:

Name	Type	Description	Default
analysis_results	WorkflowResult	The analysis workflow results.	required
qubits	QuantumElements	The qubits to run the experiments on.	required
evaluation_parameters	dict[str, Any] | None	The evaluation parameters.	None

Returns:

Type	Description
dict[str, dict[str, bool]]	The evaluation flags.

experiment_workflow(session, qpu, qubits, *, delays, evaluation_parameters=None, temporary_parameters=None, options=None)

The lifetime_measurement experiment Workflow.

The workflow consists of the following steps:

• create_experiment
• compile_experiment
• run_experiment
• analysis_workflow
• evaluate_experiment
• update_qpu

Changed in version 26.4.0.

The evaluation_parameters argument has been added, which is the dictionary of parameters used for the newly added evaluation task. All arguments apart from session, qpu, and qubits are now keyword arguments.

Deprecated in version 26.1.0.

The qubits argument of type QuantumElements is deprecated. Please pass qubits of type list[str] | str instead, i.e., the quantum element UIDs instead of the quantum element instances.

Parameters:

Name	Type	Description	Default
session	Session	The connected session to use for running the experiment.	required
qpu	QPU	The qpu consisting of the original qubits and quantum operations.	required
qubits	QuantumElements | list[str] | str	The qubits to run the experiments on, passed by UID. May be either a single qubit or a list of qubits.	required
delays	QubitSweepPoints	The delays to sweep over for each qubit. If qubits is a single qubit, delays must be a list of numbers or an array. Otherwise it must be a list of lists of numbers or arrays.	required
evaluation_parameters	dict[str, Any] | None	The dictionary of parameters used for the evaluation task. The default evaluation parameters are defined in the evaluate_experiment task.	None
temporary_parameters	dict[str | tuple[str, str, str], dict | QuantumParameters] | None	The temporary parameters with which to update the quantum elements and topology edges. For quantum elements, the dictionary key is the quantum element UID. For topology edges, the dictionary key is the edge tuple (tag, source node UID, target node UID).	None
options	TuneUpWorkflowOptions | None	The options for building the workflow. In addition to options from [WorkflowOptions], the following custom options are supported: - create_experiment: The options for creating the experiment.	None

Returns:

Name	Type	Description
result	None	The result of the workflow.

Example

options = TuneUpWorkflowOptions()
options.create_experiment.count = 10
options.create_experiment.transition = "ge"
setup = DeviceSetup("my_device")
qpu = QPU(
    quantum_elements=[TunableTransmonQubit("q0"), TunableTransmonQubit("q1")],
    quantum_operations=TunableTransmonOperations(),
)
temp_qubits = qpu.copy_quantum_elements()
result = run(
    session=session,
    qpu=qpu,
    qubits=temp_qubits,
    delays=[[10e-9, 50e-9, 1], [10e-9, 50e-9, 1]],
    options=options,
)