qoolqit.drive

drive

Classes:

• DetuningMapModulator –

  A weighted detuning for the Detuning Map Modulator (DMM).

• Drive –

  The drive Hamiltonian acting over a duration.

DetuningMapModulator(waveform: Waveform, weights: dict[Any, float]) dataclass

A weighted detuning for the Detuning Map Modulator (DMM).

Parameters:

waveform

(Waveform) –

The waveform for this detuning. Must be negative for all times.

weights

(dict[Any, float]) –

A dictionary associating detuning weights to qubits. Each weight must be in [0, 1], where 0 means that the waveform is ignored for this qubit and 1 means that the waveform is fully applied to this qubit.

See https://docs.pasqal.com/pulser/tutorials/dmm/ (external) for details on DMM.

Used by:

• API reference
  • qoolqit  qoolqit  Drive
  • qoolqit.drive  drive  Drive

Drive(*, amplitude: Waveform, detuning: Waveform | None = None, dmm: DetuningMapModulator | None = None, phase: float = 0.0)

The drive Hamiltonian acting over a duration.

The Drive specifies the control parameters for the time-dependent drive Hamiltonian in the Rydberg model (see https://docs.pasqal.com/qoolqit/get_started/qoolqit_model/ (external) for details),

H_drive(t) = Σᵢ [Ω(t)/2 (cos φ(t) σˣᵢ - sin φ(t) σʸᵢ)] - Σᵢ [δ(t) + εᵢ Δ(t)] nᵢ

representing: - Amplitude Ω(t): Controls the Rabi frequency that drives qubits. - Detuning δ(t): Controls the energy offset of the Rydberg state. - dmm εᵢ, Δ(t): Detuning Map Modulator (DMM) for additional qubit-specific detunings. - Phase φ: Global phase applied to the amplitude term.

Parameters:

amplitude

(Waveform) –

Time-dependent amplitude waveform Ω(t) representing the Rabi frequency. Controls the strength of the coupling between ground and Rydberg states. Must be positive for all times.

detuning

(Waveform | None, default:None) –

Time-dependent detuning waveform δ(t) representing the energy offset of the Rydberg state relative to resonance. If None, defaults to zero detuning (Delay waveform) for the duration of the amplitude.

dmm

(DetuningMapModulator | None, default:None) –

DetuningMapModulator instance for additional negative detuning waveform Δ(t) ≤ 0 applied to individual qubits as specified by its weights attribute εᵢ.

phase

(float, default:0.0) –

Global phase φ applied to the amplitude term in the Hamiltonian. Defaults to 0.0 (no phase).

Raises:

• TypeError –

  If amplitude or detuning are not Waveform instances.

• ValueError –

  If the amplitude waveform has negative values.

Note

Example

Used by:

• API reference
  • qoolqit  qoolqit
    •  QuantumProgram
    •  SequenceCompiler
  • qoolqit.execution  execution  SequenceCompiler
  • qoolqit.program  program  QuantumProgram

Attributes:

• amplitude (Waveform) –

  The amplitude waveform in the drive.

• detuning (Waveform) –

  The detuning waveform in the drive.

• dmm (DetuningMapModulator | None) –

  Detuning Map Modulator (DMM) applied to individual qubits.

• phase (float) –

  The phase value in the drive.

Source code in qoolqit/drive.py

def __init__(
    self,
    *,
    amplitude: Waveform,
    detuning: Waveform | None = None,
    dmm: DetuningMapModulator | None = None,
    phase: float = 0.0,
) -> None:
    """Initialize a Drive.

    The Drive specifies the control parameters for the time-dependent drive Hamiltonian
    in the Rydberg model
    (see https://docs.pasqal.com/qoolqit/get_started/qoolqit_model/ for details),

    H_drive(t) = Σᵢ [Ω(t)/2 (cos φ(t) σˣᵢ - sin φ(t) σʸᵢ)] - Σᵢ [δ(t) + εᵢ Δ(t)] nᵢ

    representing:
    - Amplitude Ω(t): Controls the Rabi frequency that drives qubits.
    - Detuning δ(t): Controls the energy offset of the Rydberg state.
    - dmm εᵢ, Δ(t): Detuning Map Modulator (DMM) for additional qubit-specific detunings.
    - Phase φ: Global phase applied to the amplitude term.

    Args:
        amplitude: Time-dependent amplitude waveform Ω(t) representing the Rabi frequency.
            Controls the strength of the coupling between ground and Rydberg states.
            Must be positive for all times.
        detuning: Time-dependent detuning waveform δ(t) representing the energy offset
            of the Rydberg state relative to resonance. If None, defaults to zero
            detuning (Delay waveform) for the duration of the amplitude.
        dmm: DetuningMapModulator instance for additional negative detuning waveform Δ(t) ≤ 0
            applied to individual qubits as specified by its `weights` attribute εᵢ.
        phase: Global phase φ applied to the amplitude term in the Hamiltonian.
            Defaults to 0.0 (no phase).

    Raises:
        TypeError: If amplitude or detuning are not Waveform instances.
        ValueError: If the amplitude waveform has negative values.

    Note:
        - All arguments must be passed as keyword arguments.
        - If amplitude and detuning have different durations, the shorter one is
          automatically extended with a Delay to match the longer duration.
        - DetuningMapModulator waveform must be negative for all times
            (≤ 0) as it represents energy shifts below the resonance.

    Example:
        >>> from qoolqit import Drive
        >>> from qoolqit.waveforms import Constant, Ramp
        >>>
        >>> # Simple constant drive
        >>> drive = Drive(amplitude=Constant(10.0, 1.5))
        >>>
        >>> # Drive with time-varying amplitude and detuning
        >>> amp = Ramp(5.0, 0.0, 2.0)
        >>> det = Constant(5.0, -1.0)
        >>> drive = Drive(amplitude=amp, detuning=det, phase=0.5)
    """

    for arg in [amplitude, detuning]:
        if arg is not None and not isinstance(arg, Waveform):
            raise TypeError("'amplitude' and 'detuning' must be of type Waveform.")

    if amplitude.min() < 0.0:
        raise ValueError("'amplitude' must be positive.")

    self._amplitude = amplitude
    self._detuning = detuning if detuning is not None else Delay(amplitude.duration)

    self._amplitude_orig = self._amplitude
    self._detuning_orig = self._detuning

    # adjust amplitude and detuning waveforms to match the duration
    if self._amplitude.duration > self._detuning.duration:
        extra_duration = self._amplitude.duration - self._detuning.duration
        self._detuning = CompositeWaveform(self._detuning, Delay(extra_duration))
    elif self._detuning.duration > self._amplitude.duration:
        extra_duration = self._detuning.duration - self._amplitude.duration
        self._amplitude = CompositeWaveform(self._amplitude, Delay(extra_duration))

    self._duration = self._amplitude.duration
    if dmm is not None and not isinstance(dmm, DetuningMapModulator):
        raise TypeError("'dmm' must be of type DetuningMapModulator.")
    self._dmm = dmm
    self._phase = phase

amplitude: Waveform property

The amplitude waveform in the drive.

detuning: Waveform property

The detuning waveform in the drive.

dmm: DetuningMapModulator | None property

Detuning Map Modulator (DMM) applied to individual qubits.

phase: float property

The phase value in the drive.