{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,9]],"date-time":"2026-10-09T12:42:15Z","timestamp":1791549735227,"version":"4.3.4"},"reference-count":37,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T00:00:00Z","timestamp":1772323200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Innovation Program for Quantum Science and Technology","award":["2021ZD0300403"],"award-info":[{"award-number":["2021ZD0300403"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>Surface collisions at Pyrex walls limit the spin coherence in nuclear magnetic resonance gyroscopes (NMRG) vapor cells, while the cavity\u2013stem junction introduces geometry dependent exchange that perturbs the transverse spin relaxation time T2 of 129Xe atoms. We combine T2 measurements with Monte Carlo simulations of confined diffusion and surface collisions to decompose the relaxation of Xe atoms and derive a cavity\u2013stem geometry correction for wall relaxation. A structural coupling factor (SCF) is introduced to compress stem length and aperture diameter into a dimensionless metric for diffusion-limited mixing, enabling prediction of the transverse relaxation rate versus geometry. Across eight simulated configurations, the model yields R2=0.982 and agrees with experiments within 7\u20139%, comparable to the measurement uncertainty (\u00b10.015s\u22121). Using the validated framework, geometry optimization reduces the relaxation rate from 0.225 to 0.131s\u22121 (a 41.8% improvement). This Pyrex surface-collisional analysis provides an in-situ, T2-based route to compare effective surface depolarization across fabrication and surface-treatment protocols while accounting for cavity\u2013stem coupling.<\/jats:p>","DOI":"10.3390\/ma19050956","type":"journal-article","created":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T14:19:21Z","timestamp":1772720361000},"page":"956","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Surface-Collision Analysis of Microscale-Confined 129Xe in Pyrex Vapor Cells Based on Stem-Transport and Gradient Diffusion Dynamics"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-5708-9466","authenticated-orcid":false,"given":"Shangtao","family":"Jiang","sequence":"first","affiliation":[{"name":"School of Instrumentation and Optoelectronics Engineering, Beihang University, Beijing 100191, China"},{"name":"Hangzhou Innovation Institute, Beihang University, Hangzhou 310052, China"},{"name":"Hefei National Laboratory, Hefei 230088, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tengyue","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Instrumentation and Optoelectronics Engineering, Beihang University, Beijing 100191, China"},{"name":"Hangzhou Innovation Institute, Beihang University, Hangzhou 310052, China"},{"name":"Hefei National Laboratory, Hefei 230088, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-2125-347X","authenticated-orcid":false,"given":"Xuyang","family":"Qiu","sequence":"additional","affiliation":[{"name":"Hangzhou Innovation Institute, Beihang University, Hangzhou 310052, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8381-3960","authenticated-orcid":false,"given":"Heng","family":"Yuan","sequence":"additional","affiliation":[{"name":"School of Instrumentation and Optoelectronics Engineering, Beihang University, Beijing 100191, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,3,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"230801","DOI":"10.1103\/PhysRevLett.95.230801","article-title":"Nuclear Spin Gyroscope Based on an Atomic Comagnetometer","volume":"95","author":"Kornack","year":"2005","journal-title":"Phys. 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