Photonic crystals (PCs) based on porous anodic materials have been proven to be a potent and versatile instrument for the emergence of new technologies with a wide range of applications. Their lower production costs are one of the key advantages, making PC-based systems more widely available and appropriate for industrial manufacturing. The ability to produce well-defined pores on metal oxide and semiconductor surfaces has experienced a major renaissance due to the striking differences in characteristics between porous surfaces and dense oxide layers. In this review, we give a general overview of the progress of PC fabrication based on porous surfaces of anodized aluminum (Al), silicon (Si), and titanium (Ti) using various anodization techniques, and their optical characteristics and applications are discussed. The anodizing conditions have a large influence on the pore geometry of the produced porous surfaces. The review fully focuses on the advancements made in manufacturing anodic aluminum oxide (AAO), porous silicon (pSi), and titanium-dioxide nanotube (TNT) PCs manufactured using self-ordered anodization under varied conditions. Additionally, a critical assessment of the upcoming developments in PC manufacturing and their optical characteristics suitable for various photonic devices is provided.

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A modality to high tunability and sensing performance of one-dimensional (1D) topological photonic crystal (PC) heterostructure is realized based on a new mechanism through 1D topological PC. With inserting a defect aqueous layer as a sandwich between two 1D PCs, the transmittance gradually decreases with the increasing thickness of the defect layer. When the two layers of the topological heterostructure interface are replaced by the defect layer, the tunability, all sensing capabilities have been improved and the principle of topology is preserved. A topologically protected edge state is formed at the heterostructure interface with a highly localized electric field. For glucose sensing, high sensitivity S = 603.753 nm/RIU is obtained at the low detection limit of about DL = 1.22×10^(-4) RIU with high-quality factor Q = 2.33×10^4 and a high figure of merit FOM = 8147.814 RIU^(-1). Besides, the transmittance can be maintained more than 99% at low and/or high glucose concentrations, due to the coupling topological edge mode between defect mode and topological edge state. An excellent platform is examined for the design of a topological photonic sensor which is a flexible platform that can be used for any type of sensor solely by replacing the interface layers with the sensor materials. Thus, our results will promote the development of 1D topological photonic devices.

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