By Monica Hernandez

This article is also available in Spanish.

To continue reading in Spanish, visit: El Advanced Quantum Testbed En Berkeley Lab Lidera Avances Científicos

The Advanced Quantum Testbed (AQT) at Lawrence Berkeley National Laboratory (Berkeley Lab) is a state-of-the-art quantum computing research laboratory funded by the U.S. Department of Energy (DOE) Office of Science Advanced Scientific Computing Research program. Based on superconducting circuits, the laboratory builds on the decades-long research and development at Berkeley Lab and benefits from DOE’s Office of Science investments in Berkeley Lab’s growing quantum information science and technology portfolio.

AQT also operates an open-access experimental testbed designed for deep collaboration with external users from academia, National Laboratories, and industry. Testbed users are selected through a peer-reviewed proposal process every year, gaining full low-level access to the testbed, including detailed data on architecture, operation, and performance. The third annual call is currently open, with Letters of Intent due October 14, 2022. The interactive collaborations and partnerships allow broad exploration of novel science at AQT with systems engineering suitable for scientific applications that rely on gate-based quantum computing.

“With this cutting-edge testbed, we are asking and evaluating the basic science questions needed to guide the future development of quantum computers,” said Irfan Siddiqi, AQT director.

Since its inception in 2018, AQT’s diverse and growing team at Berkeley Lab includes staff and postdoctoral researchers specialized in firmware and software, quantum algorithms, quantum processing units, and controls, as well as experts, graduate students, and undergraduate interns from the University of California, Berkeley. In addition, collaborating staff at AQT include researchers from MIT Lincoln Laboratory.

“The testbed also allows early-career scientists and students to access world-class quantum computing hardware and software systems, establishing a unique environment for active mentoring, open discussion, and networking between stakeholders in the quantum ecosystem,” said David I. Santiago, AQT’s technical lead.

AQT has led many significant experimental advances in a broad range of topics in four years. Some of the scientific breakthroughs published in the peer-reviewed literature include:

Classical Controls for Quantum Processors

Quantum information processors require expensive electronic controls that can manipulate qubits with precision. However, developing the control hardware that maximizes quantum computers’ performance is a theoretical and experimental challenge. AQT researchers are tackling these challenges by designing modular control hardware for current and future superconducting processors and open-sourcing the system’s full-stack software so that it can be accessed, improved, and leveraged by the broader quantum information science community. Read more:

Open Sourced Control Hardware for Quantum Computers

How a Novel Radio Frequency Control System Enhances Quantum Computers

Improved Error Characterization, Benchmarking, and Mitigation Methods

AQT researchers, in collaboration with testbed users, showed that an experimental method known as randomized compiling (RC) can dramatically reduce error rates in quantum algorithms and lead to more accurate and stable quantum computations. Using a four-qubit superconducting quantum processor, they demonstrated that RC can suppress one of the most severe types of errors in quantum computers: coherent errors. Continue reading:

Crucial Leap in Error Mitigation for Quantum Computers

AQT researchers demonstrated an error characterization method — randomized benchmarking — on a superconducting qutrit quantum processor, marking a significant milestone toward benchmarking the accuracy of qutrit-based quantum devices and identifying the barriers to overcome in future research. Learn more:

Raising the Bar in Error Characterization for Qutrit-Based Quantum Computing

Novel Logic Gates and Optimized Networks

AQT researchers developed the first 3-qubit high-fidelity iToffoli native gate in a superconducting quantum information processor and in a single step. This demonstration adds a novel easy-to-implement native three-qubit logic gate for universal quantum computing. Continue reading:

Breakthrough in Quantum Universal Gate Sets: A High-Fidelity iToffoli Gate

In partnership with the startup (acquired by ColdQuanta), researchers proved how a smart compiler specifically tailored for superconducting hardware can optimize circuits, gates, and networks and execute less error-prone quantum algorithms such as Quantum Approximate Optimization Algorithm (QAOA). Related reading: ​​

Optimizing SWAP Networks for Quantum Computing

To read more about AQT, including the latest preprints and this year’s third annual call for user proposals, visit:

Founded in 1931 on the belief that the biggest scientific challenges are best addressed by teams, Lawrence Berkeley National Laboratory and its scientists have been recognized with 16 Nobel Prizes. Today, Berkeley Lab researchers develop sustainable energy and environmental solutions, create useful new materials, advance the frontiers of computing, and probe the mysteries of life, matter, and the universe. Scientists from around the world rely on the Lab’s facilities for their own discovery science. Berkeley Lab is a multiprogram national laboratory, managed by the University of California for the U.S. Department of Energy’s Office of Science.

DOE’s Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit