Conformal integration of multifunctional nanomembranes on fibers towards intelligent optical platform

Integrating materials onto optical fibers, enabling optical signal tuning during low-loss light transmission, is essential in optical communications, biosensors, and implantable devices. Such tuning, based on light-matter interaction, requires tight physical and optical contact between materials and fibers. However, large surface curvature (>10⁵ m^-1) of fiber makes it challenging for most materials to transfer onto fibers with tight contact, due to insufficient small-range forces. This induces weak light-matter interaction and ineffective optical coupling. Here, we propose a general strategy for conformal integration of nanomembranes-including metals, oxides, semiconductors, and polymers-onto microfibers. This integration relies on engineered elastic and surface energies between nanomembranes and fibers, enabling tight wrapping. We demonstrate homogeneous and inhomogeneous nanomembranes conformally integrated on microfibers, which are further developed into sensors, modulators, filters, and photodetectors as plug-and-play devices. Our study provides a versatile platform for integrating multifunctional materials on fibers, enabling health monitoring and on-fiber photonic computing.