Source code for qibocal.protocols.coherence.t1_flux

from dataclasses import dataclass, field

import numpy as np
import numpy.typing as npt
import plotly.graph_objects as go
from qibolab import AcquisitionType, AveragingMode, Parameter, Pulse, Sweeper

from qibocal.auto.operation import Data, Parameters, QubitId, Results, Routine
from qibocal.calibration import CalibrationPlatform
from qibocal.result import probability

from ...config import log
from ..utils import COLORBAND, COLORBAND_LINE, HZ_TO_GHZ
from .t1_signal import t1_sequence
from .utils import single_exponential_fit


[docs] @dataclass class T1FluxParameters(Parameters): """T1 runcard inputs.""" delay_min: int """Initial delay before readout [ns].""" delay_max: int """Final delay before readout [ns].""" delay_step: int """Step delay before readout [ns].""" amplitude_min: float """Flux pulse minimum amplitude.""" amplitude_max: float """Flux pulse maximum amplitude.""" amplitude_step: float """Flux pulse amplitude step.""" @property def delay_range(self) -> npt.NDArray: """Return the delay range as a numpy array.""" return np.arange(self.delay_min, self.delay_max, self.delay_step) @property def flux_range(self) -> npt.NDArray: """Return the flux pulse amplitude range as a numpy array.""" return np.arange( self.amplitude_min, self.amplitude_max + self.amplitude_step, self.amplitude_step, )
[docs] @dataclass class T1FluxResults(Results): """T1 outputs.""" t1: dict[QubitId, list[float]] = field(default_factory=dict)
[docs] @dataclass class T1FluxData(Data): """T1 acquisition outputs.""" flux_range: list[float] = field(default_factory=list) """Flux pulse amplitude range [a.u.].""" wait_range: list[float] = field(default_factory=list) """Delay between pulses range [ns].""" detuning: dict[QubitId, float] = field(default_factory=dict) """DETUNING of the qubit as a function of flux pulse amplitude.""" data: dict[QubitId, npt.NDArray] = field(default_factory=dict) """Raw data acquired."""
[docs] def probability(self, qubit: QubitId) -> npt.NDArray: """Return the probability data for a specific qubit.""" return probability(self.data[qubit], state=1)
[docs] def error(self, qubit: QubitId) -> npt.NDArray: """Return the error data for a specific qubit.""" probs = self.probability(qubit) nshots = self.data[qubit].shape[0] return np.sqrt(probs * (1 - probs) / nshots)
[docs] def _acquisition( params: T1FluxParameters, platform: CalibrationPlatform, targets: list[QubitId] ) -> T1FluxData: """Data acquisition for T1 flux experiment.""" sequence, ro_pulses, pulses = t1_sequence( platform=platform, targets=targets, flux_pulse_amplitude=0.5 ) for qubit in targets: assert ( platform.calibration.single_qubits[qubit].qubit.flux_coefficients is not None ), f"Qubit {qubit} flux coefficients not set in calibration." sweeper_delay = Sweeper( parameter=Parameter.duration, values=params.delay_range, pulses=pulses, ) sweeper_amplitude = Sweeper( parameter=Parameter.amplitude, values=params.flux_range, pulses=[pulse for pulse in pulses if isinstance(pulse, Pulse)], ) _data = {} results = platform.execute( [sequence], [[sweeper_amplitude], [sweeper_delay]], nshots=params.nshots, relaxation_time=params.relaxation_time, acquisition_type=AcquisitionType.DISCRIMINATION, averaging_mode=AveragingMode.SINGLESHOT, ) for qubit in targets: _data[qubit] = results[ro_pulses[qubit].id] data = T1FluxData( data=_data, wait_range=params.delay_range.tolist(), flux_range=params.flux_range.tolist(), detuning={ qubit: ( platform.config(platform.qubits[qubit].drive).frequency * HZ_TO_GHZ + platform.calibration.single_qubits[qubit].qubit.detuning( params.flux_range ) ).tolist() for qubit in targets }, ) return data
[docs] def _fit(data: T1FluxData) -> T1FluxResults: """Fitting procedure fot T1 flux experiment. For each detuning value we compute the T1 time using a single exponential fit.""" t1s = {qubit: [] for qubit in data.qubits} for qubit in data.qubits: prob = data.probability(qubit) error = data.error(qubit) for i in range(len(data.detuning[qubit])): try: t1, _, _, _ = single_exponential_fit( np.array(data.wait_range), prob[i], error[i], zeno=False ) t1s[qubit].append(t1) except Exception as e: log.warning( f"T1 fitting failed for qubit {qubit} and amplitude {data.flux_range[i]} due to {e}." ) t1s[qubit].append(np.nan) return T1FluxResults(t1=t1s)
[docs] def _plot(data: T1FluxData, target: QubitId, fit: T1FluxResults = None): """Plotting function for T1 flux experiment.""" fig = go.Figure() if fit is not None: indices = list(set(np.where(np.array(fit.t1[target]) != np.nan)[0])) t1s = np.array([fit.t1[target][i][0] for i in indices]) error = np.array([fit.t1[target][i][1] for i in indices]) detuning = np.array(data.detuning[target])[indices] fig.add_traces( [ go.Scatter( x=detuning, y=t1s, opacity=1, name="T1", showlegend=True, legendgroup="T1", mode="lines", ), go.Scatter( x=np.concatenate((detuning, detuning[::-1])), y=np.concatenate((t1s + error, (t1s - error)[::-1])), fill="toself", fillcolor=COLORBAND, line=dict(color=COLORBAND_LINE), showlegend=True, name="Errors", ), ] ) fig.update_layout( xaxis_title="Frequency [GHz]", yaxis_title="T1 [ns]", yaxis=dict(range=[0, max(t1s) * 1.2]), xaxis=dict(range=[min(data.detuning[target]), max(data.detuning[target])]), ) return [fig], ""
t1_flux = Routine(_acquisition, _fit, _plot) """T1 flux Routine object."""