Seminar: A Systems Approach to Fault-Tolerant Quantum Computing

_Abstract

We are beginning a remarkably exciting time for quantum computing. There is a growing consensus that quantum error correction (QEC) is needed to reach scales necessary for quantum advantage, and recent major demonstrations have led to a new generation of error-corrected quantum computers. These demonstrations transition QEC from a theoretical idea introduced in 1995 to an experimental reality. Underlying this milestone is rapid progress in the scale of quantum hardware, with systems today featuring up to 1,000 qubits and error rates nearing 0.1%. However, looking towards the future, significant work is still needed to organize and scale quantum hardware to create fault-tolerant quantum computers (FTQC) capable of practical quantum advantage.

While the theory of FTQC is promising, effectively connecting it to real devices poses significant challenges. In this talk, I will discuss the role of systems and architecture research in efficiently addressing these challenges, focusing on two examples of my work. First, I will describe the problems involved in large-scale, real-time QEC decoding, and detail a speculative window decoder that reduces decoder reaction time by up to 50%. Second, I will show how insights from decoding lead to a heuristic for compiling QEC codes that reduces logical error rates by 2.5x-4x and helps automate QEC design space exploration.Together, these works fit into a larger vision on a full-stack view of FTQC and highlight opportunities for interdisciplinary, systems-level research to accelerate the realization of large-scale quantum computing.

_Biography

Joshua Viszlai is a Ph.D. student at the University of Chicago advised by Fred Chong. His research spans both theory and experiment with a focus on bridging the gap between current quantum devices and fault-tolerant quantum computing. His work has been implemented in quantum hardware and has been published in top-tier conferences in the fields of computer architecture and quantum computing leading to two best paper awards and a best poster honorable mention award. Joshua is also a consultant at lnfleqtion, a company developing neutral atom quantum computers, where he helps lead research on quantum error correction.