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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 Qubits

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()
qpu = QPU(
    setup=DeviceSetup("my_device"),
    qubits=[TunableTransmonQubit("q0"), TunableTransmonQubit("q1")],
    quantum_operations=TunableTransmonOperations(),
)
temp_qubits = qpu.copy_qubits()
create_experiment(
    qpu=qpu,
    qubits=temp_qubits,
    delays=[[10e-9, 50e-9, 1], [10e-9, 50e-9, 1]],
    options=options,
)

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

The lifetime_measurement experiment Workflow.

The workflow consists of the following steps:

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 Qubits

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, delays must be a list of numbers or an array. Otherwise it must be a list of lists of numbers or arrays.

required
temporary_parameters dict[str, dict | TransmonParameters] | None

The temporary parameters to update the qubits with.

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"
qpu = QPU(
    setup=DeviceSetup("my_device"),
    qubits=[TunableTransmonQubit("q0"), TunableTransmonQubit("q1")],
    quantum_operations=TunableTransmonOperations(),
)
temp_qubits = qpu.copy_qubits()
result = run(
    session=session,
    qpu=qpu,
    qubits=temp_qubits,
    delays=[[10e-9, 50e-9, 1], [10e-9, 50e-9, 1]],
    options=options,
)