Q-CTRL Quantifies the Benefit of Their Qubit Control Software using the QED-C Application Benchmarks

Q-CTRL has long claimed that their qubit control software can provide improve gate fidelities and now has supplied data that can show how well it works. They have used the QED-C application benchmarks that we reported on earlier this month, and re-ran some of the tests on a few IBM superconducting quantum computers to show improved results. They used their upcoming Fire Opal toolset which will provide optimized control pulses to implement the gates on the IBM Lagos quantum computer which has seven qubits and a quantum volume of 32. This results in superior implementation of the gates with higher gate fidelities than can be achieved with the unmodified standard gates. They achieved an improved result fidelity of about 1.6X for the Grover's Search algorithm, about 12X for the Quantum Fourier Transform and about 27X for the Bernstein-Vazirani algorithm. To be clear, this method, called error suppression, improves the fidelity of an individual physical qubit and should not be confused with quantum error correction that will use multiple physical qubits to implement a logical qubit.

Colormap showing the improvement in algorithmic success achieved for different algorithms examined. As you move to the right on the graphs, algorithmic performance becomes limited by hardware. Credit:: Q-CTRL

Q-CTRL's descriptions only mention they have used this approach on a few IBM superconducting machines including IBM_Jakarta (7 qubits, QV 16) and IBM_Lagos. It would be interesting to see the results of this test on some of IBM's more advanced processors that have a Quantum Volume of 128 because the benefit may not be the same for the more advanced processors. In addition, we would point out a recent blog post from IonQ showing their tests of these QED-C benchmark on their ion trap machine show result fidelities far exceeding those shown for the IBM machines even with the Q-CTRL software. It would be interesting to see if the Q-CTRL software can provide further improvements for the ion trap machines.

For more about Q-CTRL's tests and the results, you can read a press release about it here and a blog article with additional technical detail and charts here.

November 6, 2021