IBMBackend

class IBMBackend(configuration, service, api_client, instance=None)

Backend class interfacing with an IBM Quantum backend.

Note

• You should not instantiate the IBMBackend class directly. Instead, use the methods provided by an QiskitRuntimeService instance to retrieve and handle backends.

This class represents an IBM Quantum backend. Its attributes and methods provide information about the backend. For example, the status() method returns a BackendStatus instance. The instance contains the operational and pending_jobs attributes, which state whether the backend is operational and also the number of jobs in the server queue for the backend, respectively:

status = backend.status()
is_operational = status.operational
jobs_in_queue = status.pending_jobs

Here is list of attributes available on the IBMBackend class:

• name: backend name.

• backend_version: backend version in the form X.Y.Z.

• num_qubits: number of qubits.

• target: A qiskit.transpiler.Target object for the backend.

• basis_gates: list of basis gates names on the backend.

• gates: list of basis gates on the backend.

• local: backend is local or remote.

• simulator: backend is a simulator.

• conditional: backend supports conditional operations.

• open_pulse: backend supports open pulse.

• memory: backend supports memory.

• max_shots: maximum number of shots supported.

• coupling_map (list): The coupling map for the device

• supported_instructions (List[str]): Instructions supported by the backend.

• dynamic_reprate_enabled (bool): whether delay between programs can be set dynamically (ie via rep_delay). Defaults to False.

• rep_delay_range (List[float]): 2d list defining supported range of repetition delays for backend in μs. First entry is lower end of the range, second entry is higher end of the range. Optional, but will be specified when dynamic_reprate_enabled=True.

• default_rep_delay (float): Value of rep_delay if not specified by user and dynamic_reprate_enabled=True.

• n_uchannels: Number of u-channels.

• u_channel_lo: U-channel relationship on device los.

• meas_levels: Supported measurement levels.

• qubit_lo_range: Qubit lo ranges for each qubit with form (min, max) in GHz.

• meas_lo_range: Measurement lo ranges for each qubit with form (min, max) in GHz.

• dt: Qubit drive channel timestep in nanoseconds.

• dtm: Measurement drive channel timestep in nanoseconds.

• rep_times: Supported repetition times (program execution time) for backend in μs.

• meas_kernels: Supported measurement kernels.

• discriminators: Supported discriminators.

• hamiltonian: 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_circuits (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

• version: version of Backend class (Ex: 1, 2)

• channels: An optional dictionary containing information of each channel – their purpose, type, and qubits operated on.

• parametric_pulses (list): A list of pulse shapes which are supported on the backend. For example: ['gaussian', 'constant']

• processor_type (dict): Processor type for this backend. A dictionary of the form {"family": <str>, "revision": <str>, segment: <str>} such as {"family": "Canary", "revision": "1.0", segment: "A"}.

  • family: Processor family of this backend.

  • revision: Revision version of this processor.

  • segment: Segment this processor belongs to within a larger chip.

IBMBackend constructor.

Parameters:

• configuration (Union[QasmBackendConfiguration, PulseBackendConfiguration]) – Backend configuration.

• service (QiskitRuntimeService) – Instance of QiskitRuntimeService.

• api_client (BaseBackendClient) – IBM client used to communicate with the server.

Attributes

IBMBackend.coupling_map	Return the CouplingMap object
IBMBackend.dt	Return the system time resolution of input signals
IBMBackend.dtm	Return the system time resolution of output signals
IBMBackend.id_warning_issued
IBMBackend.instruction_durations	Return the InstructionDurations object.
IBMBackend.instruction_schedule_map	Return the InstructionScheduleMap for the instructions defined in this backend's target.
IBMBackend.instructions	A list of Instruction tuples on the backend of the form (instruction, (qubits)
IBMBackend.max_circuits	The maximum number of circuits
IBMBackend.meas_map	Return the grouping of measurements which are multiplexed
IBMBackend.num_qubits	Return the number of qubits the backend has.
IBMBackend.operation_names	A list of instruction names that the backend supports.
IBMBackend.operations	A list of Instruction instances that the backend supports.
IBMBackend.options	Return the options for the backend
IBMBackend.provider	Return the backend Provider.
IBMBackend.service	Return the service object
IBMBackend.target	A qiskit.transpiler.Target object for the backend.
IBMBackend.version

Methods

IBMBackend.__call__()	Call self as a function.
IBMBackend.acquire_channel(qubit)	Return the acquisition channel for the given qubit.
IBMBackend.check_faulty(circuit)	Check if the input circuit uses faulty qubits or edges.
IBMBackend.configuration()	Return the backend configuration.
IBMBackend.control_channel(qubits)	Return the secondary drive channel for the given qubit
IBMBackend.defaults([refresh])	Return the pulse defaults for the backend.
IBMBackend.drive_channel(qubit)	Return the drive channel for the given qubit.
IBMBackend.measure_channel(qubit)	Return the measure stimulus channel for the given qubit.
IBMBackend.properties([refresh, datetime])	Return the backend properties, subject to optional filtering.
IBMBackend.qubit_properties(qubit)	Return QubitProperties for a given qubit.
IBMBackend.run(*args, **kwargs)	Not supported method
IBMBackend.set_options(**fields)	Set the options fields for the backend
IBMBackend.status()	Return the backend status.
IBMBackend.target_history([datetime])	A qiskit.transpiler.Target object for the backend.