Note

This is the documentation for the current state of the development branch of Qiskit Experiments. The documentation or APIs here can change prior to being released.

InterleavedRB¶

class InterleavedRB(interleaved_element, physical_qubits, lengths, backend=None, num_samples=3, seed=None, full_sampling=False, circuit_order='RIRIRI')[source]¶

An experiment to characterize the error rate of a specific gate on a device.

Overview

Interleaved Randomized Benchmarking (RB) is a method to estimate the average error-rate of a certain quantum gate.

An interleaved RB experiment generates a standard RB sequences of random Cliffords and another sequence with the interleaved given gate. After running the two sequences on a backend, it calculates the probabilities to get back to the ground state, fits the two exponentially decaying curves, and estimates the interleaved gate error. See Ref. [1] for details.

References

[1] Easwar Magesan, Jay M. Gambetta, B. R. Johnson, Colm A. Ryan, Jerry M. Chow, Seth T. Merkel, Marcus P. da Silva, George A. Keefe, Mary B. Rothwell, Thomas A. Ohki, Mark B. Ketchen, M. Steffen, Efficient measurement of quantum gate error by interleaved randomized benchmarking, Phys. Rev. Lett. 109, 080505 (2012), doi: 10.1103/PhysRevLett.109.080505 (open)

User manual

Randomized Benchmarking

Analysis class reference

InterleavedRBAnalysis

Experiment options

These options can be set by the set_experiment_options() method.

Options

Defined in the class InterleavedRB:
- circuit_order (str)
  
  Default value: "RIRIRI"
  
  How to order the reference and the interleaved circuits. "RIRIRI" (alternate a reference and an interleaved circuit) or "RRRIII" (push all reference circuits first, then all interleaved ones).
Defined in the class StandardRB:
- lengths (List[int])
  
  Default value: None
  
  A list of RB sequences lengths.
- num_samples (int)
  
  Default value: None
  
  Number of samples to generate for each sequence length.
- seed (None or int or SeedSequence or BitGenerator or Generator)
  
  Default value: None
  
  A seed used to initialize numpy.random.default_rng when generating circuits. The default_rng will be initialized with this seed value every time circuits() is called.
- full_sampling (bool)
  
  Default value: None
  
  If True all Cliffords are independently sampled for all lengths. If False for sample of lengths longer sequences are constructed by appending additional Clifford samples to shorter sequences.
- clifford_synthesis_method (str)
  
  Default value: "rb_default"
  
  The name of the Clifford synthesis plugin to use for building circuits of RB sequences.
Defined in the class BaseExperiment:
- max_circuits (Optional[int])
  
  Default value: None
  
  The maximum number of circuits per job when running an experiment on a backend.

Example

import numpy as np
from qiskit_experiments.library import StandardRB, InterleavedRB
from qiskit_experiments.framework import ParallelExperiment, BatchExperiment
import qiskit.circuit.library as circuits

lengths = np.arange(1, 200, 30)
num_samples = 10
seed = 1010
qubits = (1, 2)

int_exp2 = InterleavedRB(
    circuits.CXGate(), qubits, lengths, num_samples=num_samples, seed=seed)

int_expdata2 = int_exp2.run(backend=backend).block_for_results()
int_results2 = int_expdata2.analysis_results()
display(int_expdata2.figure(0))

names = {result.name for result in int_results2}
print(f"Available results: {names}")

../_images/qiskit_experiments.library.randomized_benchmarking.InterleavedRB_1_0.png

Available results: {'alpha_c', '@Parameters_InterleavedRBAnalysis', 'alpha', 'EPC'}