Neutral Atom Qubits with Mark Saffman

In this episode of The New Quantum Era, host Sebastian Hassinger sits down with Dr. Mark Saffman, a leading expert in atomic physics and quantum information science. As a professor at the University of Wisconsin–Madison and Chief Scientist at Infleqtion (formerly ColdQuanta), Mark is at the forefront of developing neutral atom quantum computing platforms using Rydberg atom arrays. The conversation explores the past, present, and future of neutral atom quantum computing, its scalability, technological challenges, and opportunities for hybrid quantum systems.

Key Topics

• Evolution of Neutral Atom Quantum Computing
  The history and development of Rydberg atom arrays, key technological breakthroughs, and the trajectory from early experiments to today’s platforms capable of large-scale qubit arrays.
• Gate Fidelity and Scalability
  Advances in gate fidelity, challenges in reducing laser noise, and the inherent scalability advantages of the neutral atom platform.
• Error Correction and Logical Qubits
  Discussion of error detection/correction, logical qubit implementation, code distances, and the engineering required for repeated error correction in neutral atom systems.
• Synergy Between Academia and Industry
  The interplay between curiosity-driven university research and focused engineering efforts at Infleqtion, including the collaborative benefits of cross-pollination.
• Hybrid Quantum Systems and Future Directions
  Potential for integrating different modalities, including hybrid systems, quantum communication, and quantum sensors, as well as modularity in scaling quantum processors.

Key Insights

• Neutral atom arrays have achieved remarkable scalability, with demonstrations of arrays containing thousands of atomic qubits—well-positioned for large-scale quantum computing compared to other modalities.
• Advancements in laser technology and gate protocols have been crucial for improving gate fidelities, moving from early diode lasers to more stabilized, lower noise systems.
• Engineering challenges remain, such as atom loss, measurement speed, and the need for technologies enabling fast, high-degree-of-freedom optical reconfiguration.
• Logical qubit implementation is advancing, but practical, repeated rounds of error correction and syndrome measurement are required for fault-tolerant computing.
• Collaboration between university and industry labs accelerates both foundational understanding and the translation of discoveries into real-world devices.

Notable Quotes

1. “One of the exciting things about the Neutral Atom platform is that this is perhaps the most scalable platform that exists.”
2. “Atoms make fantastic qubits — they’re nature’s qubits, all identical, excellent coherence… but they do have some sort of annoying features. They don’t stick around forever. We have atom loss.”
3. “Our wiring is not electronic printed circuits, it’s laser beams propagating in space… That’s great because it’s reconfigurable in real time.”

About the Guest

Mark Saffman is a Professor of Physics at the University of Wisconsin–Madison and the Chief Scientist at Infleqtion, a company leading the commercial development of quantum technology platforms using neutral atoms. Mark is recognized for his pioneering work on Rydberg atom arrays, quantum logic gates, and advancing scalable quantum processors. His interdisciplinary experience bridges fundamental science and quantum tech commercialization.

Keywords: quantum computing, Rydberg atoms, neutral atom arrays, Mark Saffman, Infleqtion, gate fidelity, scalability, quantum error correction, logical qubits, hybrid quantum systems, laser cooling, quantum communication, quantum sensors, quantum advantage, optical links, atomic physics, quantum technology, academic-industry collaboration.

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