qiskit.providers.models.BackendProperties

class BackendProperties(backend_name, backend_version, last_update_date, qubits, gates, general, **kwargs)

Class representing backend properties

This holds backend properties measured by the provider. All properties which are provided optionally. These properties may describe qubits, gates, or other general propeties of the backend.

Initialize a BackendProperties instance.

Parameters

• backend_name (str) – Backend name.

• backend_version (str) – Backend version in the form X.Y.Z.

• last_update_date (datetime or str) – Last date/time that a property was updated. If specified as a str, it must be in ISO format.

• qubits (list) – System qubit parameters as a list of lists of Nduv objects

• gates (list) – System gate parameters as a list of Gate objects

• general (list) – General parameters as a list of Nduv objects

• kwargs – optional additional fields

__init__(backend_name, backend_version, last_update_date, qubits, gates, general, **kwargs)

Initialize a BackendProperties instance.

Parameters

• backend_name (str) – Backend name.

• backend_version (str) – Backend version in the form X.Y.Z.

• last_update_date (datetime or str) – Last date/time that a property was updated. If specified as a str, it must be in ISO format.

• qubits (list) – System qubit parameters as a list of lists of Nduv objects

• gates (list) – System gate parameters as a list of Gate objects

• general (list) – General parameters as a list of Nduv objects

• kwargs – optional additional fields

Methods

__init__(backend_name, backend_version, …)	Initialize a BackendProperties instance.
faulty_gates()	Return a list of faulty gates.
faulty_qubits()	Return a list of faulty qubits.
frequency(qubit)	Return the frequency of the given qubit.
from_dict(data)	Create a new Gate object from a dictionary.
gate_error(gate, qubits)	Return gate error estimates from backend properties.
gate_length(gate, qubits)	Return the duration of the gate in units of seconds.
gate_property(gate[, qubits, name])	Return the property of the given gate.
is_gate_operational(gate[, qubits])	Return the operational status of the given gate.
is_qubit_operational(qubit)	Return the operational status of the given qubit.
qubit_property(qubit[, name])	Return the property of the given qubit.
readout_error(qubit)	Return the readout error of the given qubit.
t1(qubit)	Return the T1 time of the given qubit.
t2(qubit)	Return the T2 time of the given qubit.
to_dict()	Return a dictionary format representation of the BackendProperties.

faulty_gates()

Return a list of faulty gates.

faulty_qubits()

Return a list of faulty qubits.

frequency(qubit)

Return the frequency of the given qubit.

Parameters

qubit (int) – Qubit for which to return frequency of.

Return type

float

Returns

Frequency of the given qubit.

classmethod from_dict(data)

Create a new Gate object from a dictionary.

Parameters

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

Returns

The BackendProperties from the input

dictionary.

Return type

BackendProperties

gate_error(gate, qubits)

Return gate error estimates from backend properties.

Parameters

• gate (str) – The gate for which to get the error.

• qubits (Union[int, Iterable[int]]) – The specific qubits for the gate.

Return type

float

Returns

Gate error of the given gate and qubit(s).

gate_length(gate, qubits)

Return the duration of the gate in units of seconds.

Parameters

• gate (str) – The gate for which to get the duration.

• qubits (Union[int, Iterable[int]]) – The specific qubits for the gate.

Return type

float

Returns

Gate length of the given gate and qubit(s).

gate_property(gate, qubits=None, name=None)

Return the property of the given gate.

Parameters

• gate (str) – Name of the gate.

• qubits (Union[int, Iterable[int], None]) – The qubit to find the property for.

• name (Optional[str]) – Optionally used to specify which gate property to return.

Return type

Tuple[Any, datetime]

Returns

Gate property as a tuple of the value and the time it was measured.

Raises

BackendPropertyError – If the property is not found or name is specified but qubit is not.

is_gate_operational(gate, qubits=None)

Return the operational status of the given gate.

Parameters

• gate (str) – Name of the gate.

• qubits (Union[int, Iterable[int], None]) – The qubit to find the operational status for.

Returns

Operational status of the given gate. True if the gate is operational, False otherwise.

Return type

bool

is_qubit_operational(qubit)

Return the operational status of the given qubit.

Parameters

qubit (int) – Qubit for which to return operational status of.

Return type

bool

Returns

Operational status of the given qubit.

qubit_property(qubit, name=None)

Return the property of the given qubit.

Parameters

• qubit (int) – The property to look for.

• name (Optional[str]) – Optionally used to specify within the hierarchy which property to return.

Return type

Tuple[Any, datetime]

Returns

Qubit property as a tuple of the value and the time it was measured.

Raises

BackendPropertyError – If the property is not found.

readout_error(qubit)

Return the readout error of the given qubit.

Parameters

qubit (int) – Qubit for which to return the readout error of.

Return type

float

Returns

Readout error of the given qubit,

t1(qubit)

Return the T1 time of the given qubit.

Parameters

qubit (int) – Qubit for which to return the T1 time of.

Return type

float

Returns

T1 time of the given qubit.

t2(qubit)

Return the T2 time of the given qubit.

Parameters

qubit (int) – Qubit for which to return the T2 time of.

Return type

float

Returns

T2 time of the given qubit.

to_dict()

Return a dictionary format representation of the BackendProperties.

Returns

The dictionary form of the BackendProperties.

Return type

dict