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PulseBackendConfiguration

PulseBackendConfiguration(backend_name, backend_version, n_qubits, basis_gates, gates, local, simulator, conditional, open_pulse, memory, max_shots, coupling_map, n_uchannels, u_channel_lo, meas_levels, qubit_lo_range, meas_lo_range, dt, dtm, rep_times, meas_kernels, discriminators, hamiltonian=None, channel_bandwidth=None, acquisition_latency=None, conditional_latency=None, meas_map=None, max_experiments=None, sample_name=None, n_registers=None, register_map=None, configurable=None, credits_required=None, online_date=None, display_name=None, description=None, tags=None, channels=None, **kwargs) GitHub(opens in a new tab)

Bases: qiskit.providers.models.backendconfiguration.QasmBackendConfiguration

Static configuration state for an OpenPulse enabled backend. This contains information about the set up of the device which can be useful for building Pulse programs.

Initialize a backend configuration that contains all the extra configuration that is made available for OpenPulse backends.

Parameters

  • backend_name (str) – backend name.
  • backend_version (str) – backend version in the form X.Y.Z.
  • n_qubits (int) – number of qubits.
  • basis_gates (List[str]) – list of basis gates names on the backend.
  • gates (GateConfig) – list of basis gates on the backend.
  • local (bool) – backend is local or remote.
  • simulator (bool) – backend is a simulator.
  • conditional (bool) – backend supports conditional operations.
  • open_pulse (bool) – backend supports open pulse.
  • memory (bool) – backend supports memory.
  • max_shots (int) – maximum number of shots supported.
  • coupling_map (list) – The coupling map for the device
  • n_uchannels (int) – Number of u-channels.
  • u_channel_lo (List[List[UchannelLO]]) – U-channel relationship on device los.
  • meas_levels (List[int]) – Supported measurement levels.
  • qubit_lo_range (List[List[float]]) – Qubit lo ranges for each qubit with form (min, max) in GHz.
  • meas_lo_range (List[List[float]]) – Measurement lo ranges for each qubit with form (min, max) in GHz.
  • dt (float) – Qubit drive channel timestep in nanoseconds.
  • dtm (float) – Measurement drive channel timestep in nanoseconds.
  • rep_times (List[float]) – Supported repetition times (program execution time) for backend in μs.
  • meas_kernels (List[str]) – Supported measurement kernels.
  • discriminators (List[str]) – Supported discriminators.
  • hamiltonian (Optional[Dict[str, Any]]) – An optional dictionary with fields characterizing the system hamiltonian.
  • channel_bandwidth (list) – Bandwidth of all channels (qubit, measurement, and U)
  • acquisition_latency (list) – Array of dimension n_qubits x n_registers. Latency (in units of dt) to write a measurement result from qubit n into register slot m.
  • conditional_latency (list) – Array of dimension n_channels [d->u->m] x n_registers. Latency (in units of dt) to do a conditional operation on channel n from register slot m
  • meas_map (list) – Grouping of measurement which are multiplexed
  • max_experiments (int) – The maximum number of experiments per job
  • sample_name (str) – Sample name for the backend
  • n_registers (int) – Number of register slots available for feedback (if conditional is True)
  • register_map (list) – An array of dimension n_qubits X n_registers that specifies whether a qubit can store a measurement in a certain register slot.
  • configurable (bool) – True if the backend is configurable, if the backend is a simulator
  • credits_required (bool) – True if backend requires credits to run a job.
  • online_date (datetime) – The date that the device went online
  • display_name (str) – Alternate name field for the backend
  • description (str) – A description for the backend
  • tags (list) – A list of string tags to describe the backend
  • channels (Optional[Dict[str, Any]]) – An optional dictionary containing information of each channel – their purpose, type, and qubits operated on.
  • **kwargs – Optional fields.

Methods

acquire

PulseBackendConfiguration.acquire(qubit)

Return the acquisition channel for the given qubit.

Raises

BackendConfigurationError – If the qubit is not a part of the system.

Return type

AcquireChannel

Returns

Qubit measurement acquisition line.

control

PulseBackendConfiguration.control(qubits=None, channel=None)

Return the secondary drive channel for the given qubit – typically utilized for controlling multiqubit interactions. This channel is derived from other channels.

Parameters

  • qubits (Optional[Iterable[int]]) – Tuple or list of qubits of the form (control_qubit, target_qubit).
  • channel (Optional[int]) – Deprecated.

Raises

BackendConfigurationError – If the qubits is not a part of the system or if the backend does not provide channels information in its configuration.

Return type

List[ControlChannel]

Returns

List of control channels.

describe

PulseBackendConfiguration.describe(channel)

Return a basic description of the channel dependency. Derived channels are given weights which describe how their frames are linked to other frames. For instance, the backend could be configured with this setting:

u_channel_lo = [
    [UchannelLO(q=0, scale=1. + 0.j)],
    [UchannelLO(q=0, scale=-1. + 0.j), UchannelLO(q=1, scale=1. + 0.j)]
]

Then, this method can be used as follows:

backend.configuration().describe(ControlChannel(1))
>>> {DriveChannel(0): -1, DriveChannel(1): 1}

Parameters

channel (ControlChannel) – The derived channel to describe.

Raises

BackendConfigurationError – If channel is not a ControlChannel.

Return type

Dict[DriveChannel, complex]

Returns

Control channel derivations.

drive

PulseBackendConfiguration.drive(qubit)

Return the drive channel for the given qubit.

Raises

BackendConfigurationError – If the qubit is not a part of the system.

Return type

DriveChannel

Returns

Qubit drive channel.

from_dict

classmethod PulseBackendConfiguration.from_dict(data)

Create a new GateConfig object from a dictionary.

Parameters

data (dict) – A dictionary representing the GateConfig to create. It will be in the same format as output by to_dict().

Returns

The GateConfig from the input dictionary.

Return type

GateConfig

get_channel_qubits

PulseBackendConfiguration.get_channel_qubits(channel)

Return a list of indices for qubits which are operated on directly by the given channel.

Raises

BackendConfigurationError – If channel is not a found or if the backend does not provide channels information in its configuration.

Return type

List[int]

Returns

List of qubits operated on my the given channel.

get_qubit_channels

PulseBackendConfiguration.get_qubit_channels(qubit)

Return a list of channels which operate on the given qubit.

Raises

BackendConfigurationError – If qubit is not a found or if the backend does not provide channels information in its configuration.

Return type

List[Channel]

Returns

List of Channels operated on my the given qubit.

measure

PulseBackendConfiguration.measure(qubit)

Return the measure stimulus channel for the given qubit.

Raises

BackendConfigurationError – If the qubit is not a part of the system.

Return type

MeasureChannel

Returns

Qubit measurement stimulus line.

to_dict

PulseBackendConfiguration.to_dict()

Return a dictionary format representation of the GateConfig.

Returns

The dictionary form of the GateConfig.

Return type

dict


Attributes

control_channels

Return the control channels

Return type

Dict[Tuple[int, …], List]

num_qubits

Returns the number of qubits.

In future, n_qubits should be replaced in favor of num_qubits for consistent use throughout Qiskit. Until this is properly refactored, this property serves as intermediate solution.

sample_rate

Sample rate of the signal channels in Hz (1/dt).

Return type

float

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