Innovative platforms for optical sensing: hollow-core and biodegradable optical fibers

We discuss specialty optical fibers with innovative structures, focusing on our current research efforts in hollowcore and biodegradable fibers for sensing applications. Recent advancements in hollow-core photonic crystal fibers have led to the development of low-loss fibers with simplified cross-sectional designs. We explore these fibers as sensing platforms, envisaging their applications in directional curvature, high-temperature, strain, and displacement sensors. By tuning their properties through asymmetric profiles, exploring couplings between core and cladding modes, and incorporating additional materials, these fibers demonstrated promising capabilities for optical sensing. In contrast, biodegradable optical materials offer unique advantages, such as biochemical compatibility and safe interaction with living tissues. Unlike conventional glass and plastic fibers, bioresorbable materials are typically soft, free from sharp edges, and can be absorbed or excreted after use. Here, we highlight agar-based optical optical fibers. Agar, a versatile yet underexplored material in photonics, holds significant potential for the development of environmentally friendly and biocompatible optical components.