DNA incorporated one dimensional ternary photonic crystal structures A pathway to multifunctional optical platforms

Abstract

Photonic crystals are an integral part of photonics, where light ismanipulated through carefully engineered structural features. Thesecrystals consist of periodic microstructures formed by dielectric ormetallo-dielectric materials. When light interacts with such periodicstructures, only specific frequencies are allowed to propagate, whileothers are blocked. The frequency range at which light cannot pass isknown as the photonic bandgap (PBG). Depending on the direction ofperiodic refractive index contrast between adjacent dielectric materials,photonic crystals are classified as one-dimensional (1D), two-dimensional (2D), or three-dimensional (3D). In 1D photonic crystals,light propagation is confined to a single direction. In contrast, 2D and3D structures allow light confinement in two and three directions,respectively, making them versatile in numerous optical applications,including filters, sensors, and laser devices.Among these, 1D photonic crystals stand out due to their fabricationsimplicity, making them attractive candidates in both scientific andtechnological fields. This research presents a comprehensivetheoretical and experimental analysis of 1D ternary dielectric photoniccrystals for diverse potential applications. Theoretical simulations werecarried out using the Transfer Matrix Method (TMM) and COMSOLMultiphysics software to explore the photonic band structurecharacteristics. The analysis reveals that ternary 1D structures offersignificant advantages over traditional bilayer systems, such as widerphotonic bandgaps, the emergence of multiple bandgaps, and theformation of defect modes with large Full Width at Half Maximum(FWHM).This work further investigates DNA-incorporated 1D ternary photoniccrystals and DNA-templated nanoparticles, emphasizing the dual roleof DNA as both a functional polymer layer and a templating agent fornanoparticle synthesis. DNA significantly influences surfacemorphology, nonlinear optical behavior, and the bandgap features ofthese photonic crystals. Several combinations, such asSilica/DNA/ZnO and Silica/DNA/PVA, were designed and studied.Dip-coating techniques were employed to fabricate Silica/DNA/ZnOmultilayer thin films experimentally. Theoretical models weredeveloped for systems involving other dielectric materials like aluminaandgraphiteoxide,includingconfigurationssuchasSilica/DNA/Alumina, Silica/DNA/Graphite Oxide, and GraphiteOxide/DNA/ZnO.Dielectric/DNA/Dielectric structures display remarkable features likebroad photonic bandgaps, multiple gap regions, and high oscillationdensities. Increasing the number of periods leads to enhancedoscillation density, bandgap broadening, and spectral shifts. Notably,the Silica/DNA/PVA system demonstrates promising potential for low-temperature fabrication using inkjet printing technology, paving theway for scalable three-dimensional photonic structures.Experimental studies on Silica/DNA/ZnO ternary structures werecarried out to explore their biosensing capabilities for bovine serumalbumin (BSA) and their nonlinear optical properties. Theoreticalpredictions for BSA detection showed a strong correlation withexperimental observations, validating the biosensing efficiency ofthese structures. Nonlinear optical characterization using open-apertureZ-scan revealed tunable responses in both pristine and defectivephotonic crystals. The defect layer, consisting of DNA-cappedsilicotungstate, significantly enhances the nonlinear behavior,suggesting broad applicability in advanced photonic devices.In conclusion, the investigation of 1D ternary photonic crystal systemsunderscores their significant potential across a range of photonicapplications, offering new avenues in sensing, light manipulation, andnonlinear optics