Ortega-Gomez Angel, Loyez Médéric, Lobry Maxime, Chah Karima, Zubia Joseba, Villatoro Joel, Caucheteur Christophe
Opt Express. 2021 Jun 7;29(12):18469-18480. doi: 10.1364/OE.430181.
Bare and gold-coated tilted fiber Bragg gratings (TFBGs) can nowadays be considered as a mature technology for volume and surface refractometric sensing, respectively. As for other technologies, a continuous effort is made towards the production of even more sensitive sensors, thereby enabling a high-resolution screening of the surroundings and the possible detection of rare events. To this aim, we study in this work the development of TFBG refractometers in 4-core fibers. In particular, we show that the refractometric sensitivity of the cut-off mode can reach 100 nm/RIU for a bare grating. Using another demodulation method, a tenfold sensitivity increase is obtained when tracking the extremum of the SPR (surface plasmon resonance) envelope for a gold-coated TFBG configuration. Immobilization of DNA probes was performed as a proof-of-concept to assess the high surface sensitivity of the device.
如今，裸光纤布拉格光栅（TFBG）和镀金倾斜光纤布拉格光栅分别可被视为用于体折射传感和表面折射传感的成熟技术。与其他技术一样，人们不断努力生产更灵敏的传感器，从而实现对周围环境的高分辨率筛选以及对罕见事件的可能检测。为此，我们在这项工作中研究了四芯光纤中TFBG折射仪的发展。特别是，我们表明，对于裸光栅，截止模式的折射灵敏度可达到100 nm/RIU。使用另一种解调方法，在跟踪镀金TFBG配置的SPR（表面等离子体共振）包络的极值时，灵敏度提高了十倍。进行DNA探针固定作为概念验证，以评估该装置的高表面灵敏度。
