from dataclasses import dataclass, field
from typing import Optional
import numpy as np
import numpy.typing as npt
from qibolab import AcquisitionType, AveragingMode, ExecutionParameters
from qibolab.platform import Platform
from qibolab.qubits import QubitId
from qibolab.sweeper import Parameter, Sweeper, SweeperType
from qibocal import update
from qibocal.auto.operation import Parameters, Routine
from qibocal.config import log
from qibocal.protocols.rabi.length_signal import (
RabiLengthSignalData,
RabiLengthSignalResults,
)
from ..utils import chi2_reduced, fallback_period, guess_period
from . import utils
[docs]@dataclass
class RabiLengthParameters(Parameters):
"""RabiLength runcard inputs."""
pulse_duration_start: float
"""Initial pi pulse duration [ns]."""
pulse_duration_end: float
"""Final pi pulse duration [ns]."""
pulse_duration_step: float
"""Step pi pulse duration [ns]."""
pulse_amplitude: Optional[float] = None
"""Pi pulse amplitude. Same for all qubits."""
[docs]@dataclass
class RabiLengthResults(RabiLengthSignalResults):
"""RabiLength outputs."""
chi2: dict[QubitId, list[float]] = field(default_factory=dict)
RabiLenType = np.dtype(
[("length", np.float64), ("prob", np.float64), ("error", np.float64)]
)
"""Custom dtype for rabi amplitude."""
[docs]@dataclass
class RabiLengthData(RabiLengthSignalData):
"""RabiLength acquisition outputs."""
data: dict[QubitId, npt.NDArray[RabiLenType]] = field(default_factory=dict)
"""Raw data acquired."""
[docs]def _acquisition(
params: RabiLengthParameters, platform: Platform, targets: list[QubitId]
) -> RabiLengthData:
r"""
Data acquisition for RabiLength Experiment.
In the Rabi experiment we apply a pulse at the frequency of the qubit and scan the drive pulse length
to find the drive pulse length that creates a rotation of a desired angle.
"""
sequence, qd_pulses, _, amplitudes = utils.sequence_length(
targets, params, platform
)
# define the parameter to sweep and its range:
# qubit drive pulse duration time
qd_pulse_duration_range = np.arange(
params.pulse_duration_start,
params.pulse_duration_end,
params.pulse_duration_step,
)
sweeper = Sweeper(
Parameter.duration,
qd_pulse_duration_range,
[qd_pulses[qubit] for qubit in targets],
type=SweeperType.ABSOLUTE,
)
data = RabiLengthData(amplitudes=amplitudes)
# execute the sweep
results = platform.sweep(
sequence,
ExecutionParameters(
nshots=params.nshots,
relaxation_time=params.relaxation_time,
acquisition_type=AcquisitionType.DISCRIMINATION,
averaging_mode=AveragingMode.SINGLESHOT,
),
sweeper,
)
for qubit in targets:
prob = results[qubit].probability(state=1)
data.register_qubit(
RabiLenType,
(qubit),
dict(
length=qd_pulse_duration_range,
prob=prob,
error=np.sqrt(prob * (1 - prob) / params.nshots).tolist(),
),
)
return data
[docs]def _fit(data: RabiLengthData) -> RabiLengthResults:
"""Post-processing for RabiLength experiment."""
qubits = data.qubits
fitted_parameters = {}
durations = {}
amplitudes = {}
chi2 = {}
for qubit in qubits:
qubit_data = data[qubit]
raw_x = qubit_data.length
min_x = np.min(raw_x)
max_x = np.max(raw_x)
y = qubit_data.prob
x = (raw_x - min_x) / (max_x - min_x)
period = fallback_period(guess_period(x, y))
pguess = [0.5, 0.5, period, 0, 0]
try:
popt, perr, pi_pulse_parameter = utils.fit_length_function(
x,
y,
pguess,
sigma=qubit_data.error,
signal=False,
x_limits=(min_x, max_x),
)
durations[qubit] = [pi_pulse_parameter, perr[2] * (max_x - min_x) / 2]
fitted_parameters[qubit] = popt
amplitudes = {key: [value, 0] for key, value in data.amplitudes.items()}
chi2[qubit] = [
chi2_reduced(
y,
utils.rabi_length_function(raw_x, *popt),
qubit_data.error,
),
np.sqrt(2 / len(y)),
]
except Exception as e:
log.warning(f"Rabi fit failed for qubit {qubit} due to {e}.")
return RabiLengthResults(durations, amplitudes, fitted_parameters, chi2)
[docs]def _update(results: RabiLengthResults, platform: Platform, target: QubitId):
update.drive_duration(results.length[target], platform, target)
update.drive_amplitude(results.amplitude[target], platform, target)
[docs]def _plot(data: RabiLengthData, fit: RabiLengthResults, target: QubitId):
"""Plotting function for RabiLength experiment."""
return utils.plot_probabilities(data, target, fit)
rabi_length = Routine(_acquisition, _fit, _plot, _update)
"""RabiLength Routine object."""