All-Optical Diode Action through Enhanced Nonlinear Response from Polymeric Photonic Crystal Microcavity

Abstract

The search for materials for nanophotonic devices needs a way to overcome the limitations of weak nonlinear optical response due to reduced size. The requirement of a high-power excitation source for inducing nonlinear effects in the active medium poses a hurdle in realizing all-optical and integrated optoelectronic systems. Nanosized optical materials can be embedded in photonic cavities to enhance its optical nonlinear responses through confinement effects. This report systematically investigates the linear and nonlinear optical properties of polymeric 1D-photonic crystals (PhC) with a defect layer incorporated with an imidazo-thiadiazole derivative small molecule. The nonlinear optical studies were carried out by means of a z-scan technique under nanosecond pulse using a Q-switched Nd:YAG laser operating at 532 nm. The resonant excitation creates strong confinement of light in the photonic microcavity and facilitates strong light–matter interaction that induces nonlinear response at low input intensities. A giant enhancement in the nonlinear absorption and optical limiting action was observed for PhC comparing to the bare sample. The significant enhancement in the absorptive nonlinearity is utilized for realizing a practical, on-chip, passive, all-optical diode with a PhC/Au hybrid structure. The asymmetrical nonlinear absorption of the hybrid structure exhibits non-reciprocal light transmission in the nonlinear regime. The high transmittance contrast ratio for forward/reverse bias operation and cost-effective fabrication methods makes our system a potential candidate toward the realization of compact photonic integrated devices.

Impact of Photonic Band Edge Enabled Slow Light Effect on Optical Limiting Activity of Graphene Quantum Dots in All Polymer 1-D Photonic Crystals

“…From the spectrum, it is clear that GQD emits bright blue luminescence on exciting at 330 nm, and it is due to the emission from LUMO to HOMO. 33 The morphology and size of the as-prepared GQDs were analyzed using high-resolution transmission electron microscopy (HR-TEM). TEM samples were prepared by drop casting the prepared solution on a carbon-coated copper grid, and the images were recorded using a JEOL, JEM-2100 electron microscope.…”

“…Parameters of the multilayers were optimized from the numerical analysis results using the TMM for multilayers. 33 For the simulation studies, the dispersive nature of polymers (PVK and CA), refractive index, and extinction coefficient in the visible region are taken from the literature. 34 Iterations were made before the actual PhC fabrication by controlling speed, the concentration of polymer solution, and the annealing temperature to get the best result.…”

Nonlinear Optical Studies of [Pt17(CO)12(PPh3)8]n+ Metal Nanoclusters and Their Enhancement via All-Plastic Photonic Crystal Cavity

“…Also, the cluster density and dipole coupling are greater in films than in solution . This can be fulfilled by making use of a cavity mode created at 532 nm in a photonic crystal structure. ,− …”

Hybrid Plasmonic Coupled Nanophotonic Cavity-Mediated Tunable Nonlinear Absorption in Cobalt Phthalocyanine

“…These are optical structures that can control the flow of light by the periodic variations in their refractive indices. Photonic crystals can be used to create small optical cavities that confine light in a specific region, leading to an enhancement of NLO effects. − …”