paraqeet.signal.pwc_generator.PWCGenerator#

class paraqeet.signal.pwc_generator.PWCGenerator(envelopes, tlist, max_amplitude=None)[source]#

Bases: Generator

Convert a complex envelope to PWC pulse.

This sets the pulse parameters to the tlist points. The gradient of the pulse wrt the PWC bins is 1 at that time point and zero everywhere else.

This Generator doesn’t add the LO signal to the envelope pulse. Driving with a PWC pulse (without the LO) is usually done in the rotating frame of drive.

This Generator converts the input complex pulse to the ‘in-phase’ and ‘out-of-phase’ components. This naming convention is used by following [Krantz2019]. In the literature of signal processing these are also called ‘in-phase’ and ‘quadrature’ components (refer to https://en.wikipedia.org/wiki/In-phase_and_quadrature_components).

[Krantz2019] Krantz et al., “A Quantum Engineer’s Guide to Superconducting Qubits.” Applied Physics Reviews 6(2019).

_envs: list[Waveform]: List of Envelopes
_tlist: Array: Left time points for discretization. These can be used for propagation and optimization.
_time_grid: Array: Time grid used to discretize the pulse. These are shifted from tlist by dt, and doesn’t include zero time.
_max_amplitude: float: Maximum amplitude of the drive
_inphase: Quantity: The in-phase component of the pulse
_outofphase: Quantity: The out-of-phase component of the pulse
_optimizable_paramters: list[Quantity]: List of own parameters that would be optimized by the optimizer.
_multiply_flat_top: bool: Flag to multiply flat-top-Gaussain pulse to the signal to ensure it starts and ends at zero.

Parameters:

envelopes (List[Waveform]) – List of input devices.
tlist (Array)
max_amplitude (float | None)

__init__(envelopes, tlist, max_amplitude=None)[source]#

Parameters:

envelopes (list[Waveform] | None)
tlist (Array)
max_amplitude (float | None)

Methods

`__init__`(envelopes, tlist[, max_amplitude])
`get_gradient_at_timestep`(time)	Return signal gradient wrt inphase and out-of-phase.
`get_number_of_pwc_pixels`()	Return number of PWC pixels generated by the PWC generator.
`get_parameters`()	Return a list of parameters.
`get_value`(times)	Generate the PWC signal for time(s) 't'.
`get_value_and_gradient`(times)	Return signal gradient wrt inphase and out-of-phase.
`set_all_optimizable_parameters`(all_params)	Set all optimizable parameters in the optimization.
`set_optimizable_parameters`(params)	Set specified parameters to be optimized.

Attributes

`all_optimizable_parameters`	Get the optimizable parameters
`envs`	Gets the list of envelopes.
`max_amplitude`	Get the maximum drive amplitude.
`multiply_flat_top`	Flag to multiply the pulse with a FlatTop.
`name`	Get the name of the parameter.
`optimizable_parameters`	Get the optimizable parameters
`tlist`	Get time grid discretization for generating PWC pulse.

property all_optimizable_parameters: list[Quantity]#

Get the optimizable parameters

Returns:: The list of all the optimizable parameters considered in the optimization
Return type:: list[Quantity]

property envs: list[Waveform]#

Gets the list of envelopes.

Returns:: The list of waveforms associated with the generator.
Return type:: list[Waveform]

get_gradient_at_timestep(time)[source]#

Return signal gradient wrt inphase and out-of-phase.

This returns a list of ones as the gradient of the envelope wrt a step is 1 for that time bin and 0 everywhere else.

Parameters:: time (Array) – One time step.
Returns:: PWC signal gradients.
Return type:: Array

get_number_of_pwc_pixels()[source]#

Return number of PWC pixels generated by the PWC generator.

Return type:: int

get_parameters()[source]#

Return a list of parameters.

Return the inphase and out-of-phase as parameters.

Returns:: All Parameters describing the signal.
Return type:: list[Quantity]

get_value(times)[source]#

Generate the PWC signal for time(s) ‘t’.

Parameters:: times (Array) – One-dimensional vector of timestamps.
Returns:: Returns the signal vector.
Return type:: Array

get_value_and_gradient(times)[source]#

Return signal gradient wrt inphase and out-of-phase.

This returns a list of ones as the gradient of the envelope wrt a step is 1 for that time bin and 0 everywhere else.

Parameters:: times (Array) – Array of time steps.
Returns:: PWC signal gradients.
Return type:: Array

property max_amplitude: float#

Get the maximum drive amplitude.

Return type:: The value of the maximum drive amplitude.

property multiply_flat_top: bool#

Flag to multiply the pulse with a FlatTop.

This can be used to make the start and end values zeros and force the PWC pulse to change smoothly.

Returns:: multiply_flat_top – Flag value for multiply_flat_top.
Return type:: bool

property name: str | None#

Get the name of the parameter.

Returns:: Name of the parameter.
Return type:: str | None

property optimizable_parameters: list[Quantity]#

Get the optimizable parameters

Returns:: The list of optimizable parameters associated with the object.
Return type:: list[Quantity]

set_all_optimizable_parameters(all_params)[source]#

Set all optimizable parameters in the optimization.

Parameters:

params (List[Quantity]) – List of optimizable parameters to be set.
all_params (list[Quantity])

Return type:

None

set_optimizable_parameters(params)[source]#

Set specified parameters to be optimized.

Optimizable parameters can be inphase and out-of-phase.

Parameters:: params (list[Quantity])
Return type:: None

property tlist: Array#

Get time grid discretization for generating PWC pulse.

Returns:: Array of time points at which envelope is discretized.
Return type:: Array