RZXCalibrationBuilder
class RZXCalibrationBuilder(backend=None, instruction_schedule_map=None, qubit_channel_mapping=None)
Bases: qiskit.transpiler.passes.calibration.builders.CalibrationBuilder
Creates calibrations for RZXGate(theta) by stretching and compressing Gaussian square pulses in the CX gate. This is done by retrieving (for a given pair of qubits) the CX schedule in the instruction schedule map of the backend defaults. The CX schedule must be an echoed cross-resonance gate optionally with rotary tones. The cross-resonance drive tones and rotary pulses must be Gaussian square pulses. The width of the Gaussian square pulse is adjusted so as to match the desired rotation angle. If the rotation angle is small such that the width disappears then the amplitude of the zero width Gaussian square pulse (i.e. a Gaussian) is reduced to reach the target rotation angle. Additional details can be found in https://arxiv.org/abs/2012.11660.
Initializes a RZXGate calibration builder.
Parameters
- backend (
Union[BaseBackend,BackendV1,None]) – DEPRECATED a backend object to build the calibrations for. Use of this argument is deprecated in favor of directly specifyinginstruction_schedule_mapandqubit_channel_map. - instruction_schedule_map (
Optional[InstructionScheduleMap]) – TheInstructionScheduleMapobject representing the default pulse calibrations for the target backend - qubit_channel_mapping (
Optional[List[List[str]]]) – The list mapping qubit indices to the list of channel names that apply on that qubit.
Raises
QiskitError – if open pulse is not supported by the backend.
Methods
get_calibration
RZXCalibrationBuilder.get_calibration(node_op, qubits)
Builds the calibration schedule for the RZXGate(theta) with echos.
Parameters
- node_op (
Instruction) – Instruction of the RZXGate(theta). I.e. params[0] is theta. - qubits (
List) – List of qubits for which to get the schedules. The first qubit is the control and the second is the target.
Returns
The calibration schedule for the RZXGate(theta).
Return type
schedule
Raises
QiskitError – if the control and target qubits cannot be identified or the backend does not support cx between the qubits.
name
RZXCalibrationBuilder.name()
Return the name of the pass.
rescale_cr_inst
static RZXCalibrationBuilder.rescale_cr_inst(instruction, theta, sample_mult=16)
Parameters
- instruction (
Play) – The instruction from which to create a new shortened or lengthened pulse. - theta (
float) – desired angle, pi/2 is assumed to be the angle that the pulse in the given play instruction implements. - sample_mult (
int) – All pulses must be a multiple of sample_mult.
Returns
The play instruction with the stretched compressed
GaussianSquare pulse.
Return type
qiskit.pulse.Play
Raises
QiskitError – if the pulses are not GaussianSquare.
run
RZXCalibrationBuilder.run(dag)
Run the calibration adder pass on dag.
Parameters
dag (DAGCircuit) – DAG to schedule.
Return type
DAGCircuit
Returns
A DAG with calibrations added to it.
supported
RZXCalibrationBuilder.supported(node_op, qubits)
Determine if a given node supports the calibration.
Parameters
- node_op (
Instruction) – Target instruction object. - qubits (
List) – Integer qubit indices to check.
Return type
bool
Returns
Return True is calibration can be provided.
Attributes
is_analysis_pass
Check if the pass is an analysis pass.
If the pass is an AnalysisPass, that means that the pass can analyze the DAG and write the results of that analysis in the property set. Modifications on the DAG are not allowed by this kind of pass.
is_transformation_pass
Check if the pass is a transformation pass.
If the pass is a TransformationPass, that means that the pass can manipulate the DAG, but cannot modify the property set (but it can be read).