A Loop-Shaping Approach to Coherent Feedback Control in Cavity Optomechanical Cooling

Quantum Physics [Submitted on 2 Apr 2026] A Loop-Shaping Approach to Coherent Feedback Control in Cavity Optomechanical Cooling Aoi Fujimoto, Hiroyuki Ichihara, Rina Kanamoto We present a loop-shaping approach to coherent feedback (CF) control. By formulating the coupling between a quantum system and its environment in terms of the noise power spectrum, our method enables direct manipulation of the effective dissipation coefficients through spectral shaping. A systematic design framework for CF controllers is also developed, in which transfer functions are shaped to realize desired spectral responses. Applying this framework to optomechanical sideband cooling, we demonstrate that suppression of the Stokes process and enhancement of the anti-Stokes process can be simultaneously achieved, enabling ground-state cooling even in the unresolved-sideband regime. This loop-shaping framework provides an intuitive and general foundation for the design of CF controllers and can be extended to a wide class of quantum systems in which interactions with environments are characterized by noise power spectra. Comments: 5 pages, 3 figures Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2604.01891 [quant-ph]   (or arXiv:2604.01891v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2604.01891 Focus to learn more Submission history From: Rina Kanamoto [view email] [v1] Thu, 2 Apr 2026 10:57:00 UTC (1,466 KB) Access Paper: HTML (experimental) view license Current browse context: quant-ph < prev   |   next > new | recent | 2026-04 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?)