2026-10-11T19:24:44Z https://www.scidb.cn/oai

10.57760/sciencedb.45039 2026-08-04T17:27:42Z

2026-08-04 Phonon-Engineered Indium Fluoride Glass Enabling Upconversion Fiber-Probe Infrared Sensing doi:10.57760/sciencedb.45039 en Infrared (IR) sensing in confined or occluded geometries is essential for industrial monitoring and laser safety, yet remains challenging when optical access is limited and alignment cannot be maintained. Conventional IR sensors are hindered in tortuous spaces by rigid form factors and alignment sensitivity. Here, an alignment-tolerant alternative is realized by converting IR to visible light within a low-phonon upconversion (UC) fiber and electrically reading out the emission via a fiber-integrated photodetector. Bi3+-modified InF3-based fluoride glasses exhibit a reduced maximum phonon energy (~512 to ~468 cm-1). Structural analysis and simulations reveal sixfold-coordinated, distorted Bi–F motifs with bond lengths of 2.16 and 2.50 Å, accompanied by rearrangement of the fluoride network. With 3 mol% Er3+, a maximum UC quantum yield (UCQY) of 3.2% is achieved under 980 nm excitation. The optimized glass is drawn into ≈200 μm fibers emitting at ~550 and ~650 nm. An ultrathin organic bulk-heterojunction photodetector laminated near one fiber end converts the upconverted light into an electrical signal, enabling a zero-bias UC fiber probe (UC-FP). It enables IR sensing in line-of-sight-inaccessible structures, including a 150° bent tube, and supports 2D IR mapping. These results establish a compact, alignment-tolerant route to IR sensing in complex geometries. Upconversion; Fluoride glass fiber; Low phonon energy; Bi modified; Er3+; Confined-space IR sensing 张龙飞 胡琳佳 郭子华 严婷婷 王俊新 王驰 姜益光 张龙 RESTRICTED dataset Science Data Bank