examples

Cirq Examples

The files in this directory (cirq/examples/) are examples of various quantum programs, algorithms, and demonstrations of using Cirq. This directory is not included in the packaged Cirq releases.

Tip

Everyone is free to copy, use, modify, and publish this example code under the terms of the Apache 2.0 license.

Summary of examples

Here is a summary of the examples found in this directory:

• basic_arithmetic.py: examples of various basic arithmetic circuits.
• bb84.py: demonstration of the BB84 QKD Protocol.
• bcs_mean_field.py: example of a quantum circuit to prepare the BCS ground states for superconductors/superfluids.
• bell_inequality.py: demonstration of Bell's theorem.
• bernstein_vazirani.py: demonstration of the Bernstein-Vazirani algorithm.
• deutsch.py: demonstration of Deutsch's algorithm.
• direct_fidelity_estimation.ipynb: an example that walks through the steps of running the direct fidelity estimation (DFE) algorithm
• grover.py: demonstration of Grover's algorithm.
• heatmaps.py: demonstration of how cirq.Heatmap can be used to generate a heatmap of qubit fidelities.
• hello_qubit.py: example of a simple quantum circuit.
• hhl.py: demonstration of the algorithm for solving linear systems by Harrow, Hassidim, and Lloyd.
• hidden_shift_algorithm.py: demonstration of a Hidden Shift algorithm.
• magic_square.py: demonstration of the Mermin-Peres magic square game.
• noisy_simulation_example.py: example of a noisy circuit using the cirq.ConstantQubitNoiseModel class.
• phase_estimator.py: example of a phase estimator circuit.
• qaoa.py: example of the Quantum Approximate Optimization Algorithm applied to the Max-Cut problem.
• quantum_fourier_transform.py: example of a circuit for Quantum Fourier Transform (QFT) on 4 qubits.
• quantum_teleportation.py: demonstration of a (simulation of) quantum teleportation.
• qubit_characterizations_example.py: examples of how to run various qubit characterizations.
• shor.py: demonstration of Shor's algorithm.
• shors_code.py: demonstration of Shor's code, a stabilizer code for quantum error correction.
• simon_algorithm.py: demonstration of Simon's algorithm.
• stabilizer_code.ipynb: example of quantum error correction using a stabilizer code.
• superdense_coding.py: example of superdense coding.
• swap_networks.py: demontration of swap networks.
• two_qubit_gate_compilation.py: example application of the two-qubit gate compilation algorithm.

Tips

To learn more about the examples in this directory, look inside the Python .py files for a docstring comment near the top of the file. (You can ignore the files whose names end in _test.py; those are unit tests for the example files.)

The Experiments page on the Cirq documentation site has more examples, including examples drawn from the ReCirq project.