One-Dimensional Topological Photonic Crystal Mirror Heterostructure for Sensing

Abstract

A paradigm for high-quality factor (Q) with a substantial fulfillment for appraising sensing ability and performance has been investigated. Through constructing a 1D (one-dimensional) topological photonic crystal (PhC) mirror heterostructure, which is formed by the image view of 1D topological PhC stacking with its original one. In the 1D topological PhC-mirror heterostructure, there is an interesting mode that appeared with the symmetric, typical Lorentzian-line shape with 100% transmittance in the topological mirror edge-state mode (hybrid resonance mode) at the heterostructure interface. Physically, such a mode is a defect mode, but the defect is introduced through topological operations. The high Q-factor of 5.08 × 104 is obtained due to the strong optical localization of the defect mode at the topological edge area. Consequently, this device acts as a narrow passband filter. Moreover, due to the narrow bandpass property, it may be an advantageous reference for many applications in filtering, switching, and sensing. Thus, introducing an electro-optical (EO) polymer layer at the interface to modify the edge defect can tune the defect mode both in frequency and Q-factor for higher spatial pulse compression and higher EO sensitivity. Accordingly, the Q-factor of 105, the sensitivity of 616 nm/RIU, and the figure of merit of 49,677.42 RIU−1 are obtained. The sensing ability and performance are attributable to the strong optical localization in the interface region and enhanced light-matter interaction. We predict that the 1D topological PhC mirror heterostructure will be an outstanding point in the field of optical sensing, filters, and optical switching in different fields.

Bidirectional Rainbow Trapping in 1-D Chirped Topological Photonic Crystal

“…PC 1 consists of six consecutive layers from Si and SiO 2 of layer thicknesses d 1Si 350nm, and d 1SiO 2 225nm, respectively, and the lattice constant of PC 1 is a 1 575nm. The thicknesses of PC 2 , are evaluated based on [13], are d 2SiO2 276nm and d 2Si 115nm and consists of six consecutive layers from SiO 2 and Si, respectively with a 2 391nm. The TESs can exist in TPC L (PC 1 + PC 2 ) and TPC R (PC 2 + PC 1 ) at the heterostructure interface because the two PCs possess bandgaps in the same wavelength range with different topological properties [14].…”

Tunable bidirectional perfect THz absorber realized by graphene-based one-dimensional photonic crystals

“…One-dimensional photonic crystal (1DPC) is the simplest photonic crystal structure and is easy to manufacture, which can be used to design absorbers [20][21][22][23], sensors [24][25][26] and so on [27][28][29]. In this paper, we make full use of the local properties of photonic crystals and the excellent optical properties of graphene, and propose a structure based on 1DPC and graphene which can achieve tunable multichannel perfect absorption.…”

Rotation controlled topological edge states in a trimer chain composed of meta-atoms

“…The edge states of a finite SSH chain will be distributed at both ends of the chain. Moreover, edge states with topological protection are immune to the fabrication error of the chain, which have been used to realize many applications, such as the topological lasers [27][28][29], filter [4], sensors [30,31], and wireless power transfer (WPT) [32][33][34]. Normally, the construction of SSH chain in optical systems needs to change the separation of adjacent resonators or waveguides.…”