qiskit.pulse.Drag¶

class Drag(duration, amp, sigma, beta, name=None)[Quellcode]¶

The Derivative Removal by Adiabatic Gate (DRAG) pulse is a standard Gaussian pulse with an additional Gaussian derivative component. It is designed to reduce the frequency spectrum of a normal gaussian pulse near the \(|1\rangle\) - \(|2\rangle\) transition, reducing the chance of leakage to the \(|2\rangle\) state.

\[f(x) = Gaussian + 1j * beta * d/dx [Gaussian] = Gaussian + 1j * beta * (-(x - duration/2) / sigma^2) [Gaussian]\]

where ‚Gaussian‘ is:

\[Gaussian(x, amp, sigma) = amp * exp( -(1/2) * (x - duration/2)^2 / sigma^2) )\]

References

Gambetta, J. M., Motzoi, F., Merkel, S. T. & Wilhelm, F. K. Analytic control methods for high-fidelity unitary operations in a weakly nonlinear oscillator. Phys. Rev. A 83, 012308 (2011).

F. Motzoi, J. M. Gambetta, P. Rebentrost, and F. K. Wilhelm Phys. Rev. Lett. 103, 110501 – Published 8 September 2009.

Initialize the drag pulse.

Parameter

duration (int) – Pulse length in terms of the the sampling period dt.
amp (Union[complex, ParameterExpression]) – The amplitude of the Drag envelope.
sigma (Union[float, ParameterExpression]) – A measure of how wide or narrow the Gaussian peak is; described mathematically in the class docstring.
beta (Union[float, ParameterExpression]) – The correction amplitude.
name (Optional[str]) – Display name for this pulse envelope.

__init__(duration, amp, sigma, beta, name=None)[Quellcode]¶

Initialize the drag pulse.

Parameter

duration (int) – Pulse length in terms of the the sampling period dt.
amp (Union[complex, ParameterExpression]) – The amplitude of the Drag envelope.
sigma (Union[float, ParameterExpression]) – A measure of how wide or narrow the Gaussian peak is; described mathematically in the class docstring.
beta (Union[float, ParameterExpression]) – The correction amplitude.
name (Optional[str]) – Display name for this pulse envelope.

Methods

`__init__`(duration, amp, sigma, beta[, name])	Initialize the drag pulse.
`assign_parameters`(value_dict)	Return a new ParametricPulse with parameters assigned.
`draw`([dt, style, filename, interp_method, …])	Plot the pulse.
`get_sample_pulse`()	Deprecated.
`get_waveform`()	Return a Waveform with samples filled according to the formula that the pulse represents and the parameter values it contains.
`validate_parameters`()	Validate parameters.

Attributes

`amp`	The Gaussian amplitude.
`beta`	The weighing factor for the Gaussian derivative component of the waveform.
`id`	Unique identifier for this pulse.
`parameters`	Return a dictionary containing the pulse’s parameters.
`sigma`	The Gaussian standard deviation of the pulse width.

property amp¶

The Gaussian amplitude.

Rückgabetyp: Union[complex, ParameterExpression]

assign_parameters(value_dict)¶

Return a new ParametricPulse with parameters assigned.

Parameter: value_dict (Dict[ParameterExpression, Union[ParameterExpression, float, int]]) – A mapping from Parameters to either numeric values or another Parameter expression.
Rückgabetyp: ParametricPulse
Rückgabe: New pulse with updated parameters.

property beta¶

The weighing factor for the Gaussian derivative component of the waveform.

Rückgabetyp: Union[float, ParameterExpression]

draw(dt=1, style=None, filename=None, interp_method=None, scale=1, interactive=False)¶

Plot the pulse.

Parameter

dt (float) – Time interval of samples.
style (Optional[PulseStyle]) – A style sheet to configure plot appearance
filename (Optional[str]) – Name required to save pulse image
interp_method (Optional[Callable]) – A function for interpolation
scale (float) – Relative visual scaling of waveform amplitudes
interactive (bool) – When set true show the circuit in a new window (this depends on the matplotlib backend being used supporting this)

Rückgabe

A matplotlib figure object of the pulse envelope

Rückgabetyp

matplotlib.figure

get_sample_pulse()¶

Deprecated.

Rückgabetyp: Waveform

get_waveform()[Quellcode]¶

Return a Waveform with samples filled according to the formula that the pulse represents and the parameter values it contains.

Rückgabetyp: Waveform

property id¶

Unique identifier for this pulse.

Rückgabetyp: int

property parameters¶

Return a dictionary containing the pulse’s parameters.

Rückgabetyp: Dict[str, Any]

property sigma¶

The Gaussian standard deviation of the pulse width.

Rückgabetyp: Union[float, ParameterExpression]

validate_parameters()[Quellcode]¶

Validate parameters.

Verursacht: PulseError – If the parameters passed are not valid.
Rückgabetyp: None