Kovacs-like memory effect mediated fiber Bragg grating: resembling a silica quipu

作者：Qiaochu Yang, Zhiyuan Xu, Xu Yue, Junqiu Long, Haopeng Wang, Yihan Zha, Fu-Rong Feng, Yang Ran, Bai‐Ou Guan · 发表于：Nature Communications · 年份：2025 · DOI：10.1038/s41467-025-61538-y · 被引用次数：12 · 研究领域：Advanced Fiber Optic Sensors、Photonic and Optical Devices、Photorefractive and Nonlinear Optics

In antiquity, civilizations employed stone carvings and knotted quipu cords for information preservation. Modern telecommunications rely on optical fibers - silica glass strands engineered for light transmission - yet their capacity as archival media remains untapped. This study explores a novel fiber Bragg grating (FBG) configuration exhibiting thermally programmable memory effects for optical data storage. Capitalizing on temperature-dependent spectral characteristics, we demonstrate finite spectral tuning through controlled thermal annealing, achieving irreversible spectral modifications via a light-induced stress mechanism analogous to the Kovacs memory effect in glassy materials. The engineered dual-dip FBG architecture enables multiplexed wavelength encoding, functioning simultaneously as a thermal history recorder and laser-writable data medium - mirroring the information knots of ancient quipu devices. This optical quipu concept pioneers one-dimensional photonic memory technology, opening new avenues for optical fiber applications in the information age. This work introduces a dual-dip fiber Bragg grating (FBG) with thermally programmable memory. Leveraging light-induced stress and thermal annealing, it enables irreversible spectral tuning—mimicking the Kovacs effect. The FBG serves as a laser-writable, multiplexed optical data storage medium and thermal history recorder.