Thermodynamical aspects of optically pumped dense atomic medium

Quantum Physics [Submitted on 10 Apr 2026] Thermodynamical aspects of optically pumped dense atomic medium A. F. Sousa, C. H. S. Vieira, H. M. Florez Optically Pumped Magnetometers use light to drive an atomic vapor into a Non-Equilibrium Steady State for sensing. This kind of state is achieved when spin-exchange collisions, together with optical pumping, dominate the relaxation dynamics, redistributing the atomic populations and thereby shaping the steady-state configuration. Despite the rapid advancement of atomic magnetometer technology, a comprehensive thermodynamic analysis of the state preparation is largely unexplored. We apply a thermodynamic framework to alkali atoms in a vapor cell, modeling their interactions with the pump laser and their relaxation via spin-exchange and spin-destruction collisions. We analyze how the pump rate and light polarization determine the non-equilibrium steady state, quantifying irreversibility via entropy production, assessing useful energy via ergotropy, and defining the spin-polarization efficiency. Finally, we establish a connection between metrological performance and the Quantum Fisher Information (QFI), demonstrating that a higher thermodynamic efficiency directly translates into an improved fundamental bound on magnetometer sensitivity. These results provide insights for optimizing state preparation in quantum sensors. Subjects: Quantum Physics (quant-ph) Cite as: arXiv:2604.09219 [quant-ph]   (or arXiv:2604.09219v1 [quant-ph] for this version)   https://doi.org/10.48550/arXiv.2604.09219 Focus to learn more Submission history From: Aryadine Fernandes De Sousa [view email] [v1] Fri, 10 Apr 2026 11:22:41 UTC (1,445 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?)