Maxwell Parsons (University of Washington), QISE Seminar: Engineering Qubit Control for Scalable Quantum Systems

Abstract

Quantum computing is advancing along two primary scaling paradigms: distributed quantum systems connected through entanglement networks, and increasingly large individual quantum processors. Both approaches require not only long-lived qubits, but control architectures deliberately engineered to support error correction at scale. In my laboratory, we investigate these paradigms through complementary experimental platforms: color-center quantum memories for networked architectures and reconfigurable neutral-atom arrays for large-scale processors.

In color-center systems, an optically-addressable central electronic spin coherently couples to nearby nuclear spins to form a modular quantum memory with a photonic interface, suitable for quantum networking. Here, dominant limitations arise from structured environmental spin-noise and the common fluctuator associated with optical transitions of the electronic state. We are developing control strategies tailored to this noise environment, engineering microwave and optical protocols that stabilize multi-spin registers and extend usable memory lifetimes in a manner compatible with networked error-correction schemes.

In neutral-atom systems, we explore opportunities enabled by three-dimensional qubit geometries uniquely accessible in optically trapped atom arrays. Three-dimensional connectivity offers architectural advantages for efficient error correction, but imposes stringent requirements on local optical control and crosstalk suppression. At the same time, three-dimensional geometries can enable scaling in physical qubit number due to the re-use of optical power across layers of qubits for trapping and gate control.  We are co-designing 3D neutral-atom architectures and scalable optical control hardware to match qubit geometry to fault-tolerant operation and are establishing a dedicated testbed for developing and characterizing these strategies.

Across both efforts, the central theme is control–architecture co-design: engineering qubit control systems that are intentionally matched to geometry, noise environment, and error-correction strategy.

Bio

Max Parsons is an Assistant Professor in the Department of Electrical & Computer Engineering. His research focuses on advancing quantum hardware for computing, sensing, and communication by developing scalable control of neutral atoms and solid-state quantum systems. At UW, he leads efforts in optical control of qubits and experimental testbeds for neutral atom quantum processors and spin-defect quantum memories.  Parsons completed his PhD in Physics at Harvard University in 2016, where he pioneered techniques for laser cooling and atom-resolved imaging of fermionic atoms for quantum simulation. Prior to joining UW in 2022 to develop the QT3 lab, he worked in industry on mixed-reality displays at Meta’s Reality Labs and on neutral-atom quantum computing hardware at Atom Computing. He is an inventor on more than 35 patents in quantum computing and mixed-reality technologies.