On Friday, November 7 (Eastern Time), IBM announced its selection for Phase B of the Quantum Benchmarking Initiative (QBI) under the U.S. Defense Advanced Research Projects Agency (DARPA). This marks a critical validation of the company’s roadmap for building large-scale fault-tolerant quantum computers.
QBI, launched by DARPA in 2024, aims to rigorously assess whether industrial-grade fault-tolerant quantum computers with computational value exceeding their costs can be developed by 2033 through independent third-party verification. IBM had previously been selected for Phase A in April this year. DARPA revealed that, as of November 6, 11 companies—including IBM—had advanced to Phase B, employing diverse technological approaches ranging from superconducting qubits to neutral atoms.
Jay Gambetta, Director of IBM Research, stated, "IBM’s progression to Phase B of DARPA’s QBI program is a strong endorsement of our methodology in delivering large-scale fault-tolerant quantum computers."
As part of QBI, IBM also announced a technical collaboration with quantum computing startup SEEQC to explore new methods for scaling quantum computer control systems. SEEQC plans to integrate its Single Flux Quantum (SFQ) chip control-layer technology with IBM’s cutting-edge quantum system architecture. The partnership aims to miniaturize and consolidate external classical control hardware racks by transferring components to system-on-chip (SoC) designs, enabling operation alongside quantum chips in ultra-cold dilution refrigerators.
While SEEQC investigates how SFQ control chips can enhance quantum system performance and reduce energy consumption, IBM will continue advancing its quantum development roadmap, including its large-scale fault-tolerant quantum computing efforts. Gambetta emphasized IBM’s goal to deliver a fault-tolerant quantum computer by 2029, acknowledging the engineering challenges and unresolved research hurdles in scaling such systems. He expressed enthusiasm for collaborating with SEEQC to accelerate progress toward this target.
**Three-Phase Verification System and Diverse Technological Paths**
QBI consists of three progressive phases. The six-month Phase A required participants to outline preliminary technical concepts for practical quantum computers with feasible near-term pathways. Phase B, spanning one year, demands comprehensive R&D plans, including risk identification, mitigation strategies, and prototypes for risk reduction. The final Phase C involves independent testing by DARPA’s verification team to evaluate whether the proposed quantum hardware can be built and operated as designed.
DARPA, an independent R&D agency under the U.S. Department of Defense, focuses on transformative technologies for national security. QBI adds value by providing unbiased third-party validation of participants’ progress and communicating results to U.S. government stakeholders.
The 11 companies selected for Phase B span the U.S., U.K., Canada, and Australia, employing varied qubit technologies. Alongside IBM’s modular superconducting processors, participants include IonQ and Quantinuum (trapped ions), Atom Computing and QuEra Computing (neutral atoms), and Xanadu (photonic quantum computing).
DARPA clarified that QBI is not an elimination contest but an independent assessment of each company’s technical merits. A key challenge lies in the diversity of quantum computing approaches, unlike classical computing’s dominant architectures. Multiple, single, or no participants may demonstrate viable paths to industrial-scale quantum computers within eight years.
The agency expects more teams to join future phases, with staggered entry timelines across the three stages. Subsequent advancement decisions will be announced as new teams complete contracts.