{"id":2335,"date":"2026-03-25T13:57:21","date_gmt":"2026-03-25T13:57:21","guid":{"rendered":"https:\/\/wp.optics.arizona.edu\/jsu\/?p=2335"},"modified":"2026-03-25T13:59:48","modified_gmt":"2026-03-25T13:59:48","slug":"free-space-coupled-frequency-locked-microtoroid-resonators-for-ultrasensitive-gas-phase-detection","status":"publish","type":"post","link":"https:\/\/wp.optics.arizona.edu\/jsu\/free-space-coupled-frequency-locked-microtoroid-resonators-for-ultrasensitive-gas-phase-detection\/","title":{"rendered":"Free-Space\u2013Coupled Frequency-Locked Microtoroid Resonators for Ultrasensitive Gas-Phase Detection"},"content":{"rendered":"

Happy to share our latest paper in Laser & Photonics Reviews.
\nWe demonstrate free-space\u2013coupled, frequency-locked microtoroid resonators for gas sensing\u2014overcoming the long-standing limitation of fragile fiber tapers and moving WGM sensors closer to real-world use.
\nWe accomplished:
\n\u2022 25 ppt detection limit at room temperature
\n\u2022 >10\u2077 Q factors preserved after polymer coating
\n\u2022 3 orders of magnitude improvement over prior work
\n\u2022 Compact, robust, and capable of long-duration, unattended sensing
\nUsing a mustard gas simulant (2-CEES), we show that ultrahigh sensitivity and real-world robustness can coexist.
\nThis is the first demonstration of free-space\u2013coupled WGM microtoroids for chemical sensing, opening new opportunities in defense, security, and environmental monitoring.
\nThanks to our excellent collaborators and generous sponsors.<\/p>\n

Free\u2010Space\u2010Coupled Frequency\u2010Locked Microtoroid Resonators With Reactive Polymer Functionalization for Part\u2010Per\u2010Trillion Gas Detection – Xu – Laser & Photonics Reviews – Wiley Online Library<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

Happy to share our latest paper in Laser & Photonics Reviews. We demonstrate free-space\u2013coupled, frequency-locked microtoroid resonators for gas sensing\u2014overcoming the long-standing limitation of fragile fiber tapers and moving WGM sensors closer to real-world use. We accomplished: \u2022 25 ppt detection limit at room temperature \u2022 >10\u2077 Q factors preserved after polymer coating \u2022 3 orders of magnitude improvement over<\/p>\n","protected":false},"author":36,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[],"class_list":["post-2335","post","type-post","status-publish","format-standard","hentry","category-news"],"_links":{"self":[{"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/posts\/2335","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/users\/36"}],"replies":[{"embeddable":true,"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/comments?post=2335"}],"version-history":[{"count":2,"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/posts\/2335\/revisions"}],"predecessor-version":[{"id":2339,"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/posts\/2335\/revisions\/2339"}],"wp:attachment":[{"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/media?parent=2335"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/categories?post=2335"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wp.optics.arizona.edu\/jsu\/wp-json\/wp\/v2\/tags?post=2335"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}