Characterizing non-Markovian quantum processes by fast Bayesian tomography
To push gate performance to levels beyond the thresholds for quantum error correction, it is important to characterize the error sources occurring on quantum gates. However, the characterization of non-Markovian error poses a challenge to current quantum process tomography techniques. Fast Bayesian tomography (FBT) is a self-consistent tomographic protocol that can be bootstrapped from earlier characterization knowledge and be updated in real time with arbitrary gate sequences. Here we demonstrate how FBT allows for the characterization of key non-Markovian error processes. We introduce two experimental protocols for FBT to diagnose the non-Markovian behavior of two-qubit systems on silicon quantum dots. To increase the efficiency and scalability of the experiment-analysis loop, we develop a web-based FBT software stack. To reduce experiment cost and analysis time, we also introduce a native readout method and warm boot strategy. Our results demonstrate that FBT is a useful tool for probing non-Markovian errors that can be detrimental to the ultimate realization of fault-tolerant operation on quantum computing.
Authors
- Kohei M. Itoh (ORCID: https://orcid.org/0000-0002-8153-4893)
- Arne Laucht (ORCID: https://orcid.org/0000-0001-7892-7963)
- Chih Hwan Yang (ORCID: https://orcid.org/0000-0002-8713-150X)
- Andrew S. Dzurak (ORCID: https://orcid.org/0000-0003-1389-5096)
- Wee Han Lim (ORCID: https://orcid.org/0000-0002-8821-2758)
- MengKe Feng (ORCID: https://orcid.org/0000-0002-8894-7383)
- Fay E. Hudson (ORCID: https://orcid.org/0000-0003-0134-3657)
- T. J. Evans (ORCID: https://orcid.org/0000-0002-2780-8638)
- Stephen D. Bartlett (ORCID: https://orcid.org/0000-0003-4387-670X)
- Yue Su (ORCID: https://orcid.org/0000-0002-5827-2071)
- W. Huang (ORCID: https://orcid.org/0000-0001-9996-6371)
- Robin Harper (ORCID: https://orcid.org/0000-0003-4949-8754)
- Tuomo Tanttu (ORCID: https://orcid.org/0000-0002-2832-3237)
- Nard Dumoulin Stuyck (ORCID: https://orcid.org/0000-0003-0731-7679)
- K. W. Chan (ORCID: https://orcid.org/0000-0001-8804-9893)
- André Saraiva (ORCID: https://orcid.org/0000-0002-7209-9180)
- Jonathan Y. Huang (ORCID: https://orcid.org/0000-0002-1729-3052)
- W. Gilbert
Institutions
- The University of Sydney (AU)
- Keio University (JP)
- UNSW Sydney (AU)
Publication Details
- Journal
- Physical review. A/Physical review, A
- Published
- 2025-05-14
- DOI
- https://doi.org/10.1103/physreva.111.052425
- Primary Topic
- Quantum Computing Algorithms and Architecture
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Australian Research Council
- Army Research Office