RC-HEOM Hybrid Method for Non-Perturbative Open System Dynamics

Quantum Physics [Submitted on 24 Mar 2026] RC-HEOM Hybrid Method for Non-Perturbative Open System Dynamics Po-Rong Lai, Jhen-Dong Lin, Yi-Te Huang, Po-Chen Kuo, Neill Lambert, Yueh-Nan Chen The Hierarchical equations of motion (HEOM) method is an important non-perturbative technique, allowing numerically exact treatment of open quantum systems with strong coupling and non-Markovian memory. However, its encoding of bath memory into auxiliary density operators often limits direct access to detailed bath information. In contrast, the reaction-coordinate (RC) mapping allows direct and transparent access to the dominant collective bath mode, but its perturbative and often Markovian treatment of the residual bath restricts its reliability. In this work, we introduce RC-HEOM, a hybrid method that unifies the strengths of both approaches by combining RC mapping with a fully non-perturbative HEOM description of the residual bath. RC-HEOM simultaneously retains exact non-Markovian memory and access to the RC mode, which enables analysis of system-RC information. Applying this method to the Anderson impurity models, we directly track the emergence of the Kondo singlet from the growth of the Kondo resonance and uncover a nontrivial RC-mediated coherence revival. These results demonstrate that RC-HEOM is a promising method for characterizing open quantum systems in regimes that are difficult to access with conventional master-equation methods. Comments: 7 page, 3 figure, 2 tables in main tex. 7 pages, 1 figure, 3 tables in supplemental material Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2603.22833 [quant-ph]   (or arXiv:2603.22833v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2603.22833 Focus to learn more Submission history From: Po-Rong Lai [view email] [v1] Tue, 24 Mar 2026 06:11:12 UTC (2,310 KB) Access Paper: HTML (experimental) view license Current browse context: quant-ph < prev   |   next > new | recent | 2026-03 References & Citations INSPIRE HEP NASA ADS Google Scholar Semantic Scholar Export BibTeX Citation Bookmark Bibliographic Tools Bibliographic and Citation Tools Bibliographic Explorer Toggle Bibliographic Explorer (What is the Explorer?) Connected Papers Toggle Connected Papers (What is Connected Papers?) Litmaps Toggle Litmaps (What is Litmaps?) scite.ai Toggle scite Smart Citations (What are Smart Citations?) Code, Data, Media Demos Related Papers About arXivLabs Which authors of this paper are endorsers? | Disable MathJax (What is MathJax?)