Triangle Quantum Computing Seminar Series: Improving Runtime and Accuracy of Near-term Quantum Applications via Efficient Job Scheduling in the Cloud

Variational Quantum Algorithms (VQAs), considered promising applications for near-term Noisy Intermediate-Scale Quantum (NISQ) systems, require multiple optimization iterations to converge on a globally optimal solution. Moreover, these optimizations require restarts, which basically repeat the execution from different starting points to mitigate the impact of noise. Unfortunately, quantum job scheduling policies in the cloud are heavily unoptimized for VQAs, often scheduled on a single system. Unfortunately, this presents a critical trade-off: users often prefer higher-fidelity machines to ensure higher-quality solutions, which also results in increased wait times to get access to these machines. Today, typical cloud latencies range even up to days. In this talk, I will discuss Qoncord, an automated job scheduling framework to address these cloud-centric challenges for VQAs. Qoncord leverages the insight that not all training iterations and restarts are equal, and strategically divides the training process into exploratory and fine-tuning phases. Early exploratory iterations, more resilient to noise, are executed on less busy and often more error-prone machines, while fine-tuning occurs on high-fidelity machines with longer wait times. This adaptive approach mitigates the impact of noise, optimizes resource usage, and reduces queuing delays in quantum cloud environments. Qoncord offers similar solution qualities 17.4× faster. Alternatively, it provides 13.3% better solutions for the same time budget compared to the baseline. --- Poulami Das is an Assistant Professor in Electrical and Computer Engineering at University of Texas, Austin. Her research interests include quantum computing, computer architecture, and emerging technologies. Her research has been recognized with Ralph E. Powe Junior Faculty Enhancement Award, 2024 ACM SIGMICRO Dissertation Award, 2024 ACM SIGARCH/IEEE CS TCCA Outstanding Dissertation Award Honorable Mention, Best Research Award at the DAC PhD Forum, Cleaver Award for the most outstanding PhD dissertation proposal in ECE, Georgia Tech, Best Paper Award at Computing Frontiers, Microsoft PhD Research Fellowship, and has appeared in top architecture and systems venues like ICML, MICRO, HPCA, ISCA, and ASPLOS. --- Co-hosted by the Duke Quantum Center, the NC State Quantum Initiative, and the UNC Kenan-Flagler's Rethinc. Labs.