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In this Letter, a surface wave, the Pearcey Talbot-like plasmon, which has the properties of self-imaging and multiple autofocusing, is presented as a novel, to the best of our knowledge, plasmonic bottle array generation scheme. With originality, the overall structure and the partial intensity of the plasmonic bottle array can be adjusted through the initial input, and modifying the Pearcey function enables the plasmonic bottle array to exhibit self-bending characteristics, which makes particle capture and manipulation easier and more flexible. A scheme to generate the plasmon is proposed, and we prove it by the finite-difference time-domain numerical simulations.

Replica symmetry breaking (RSB) has been introduced in a random laser to investigate the interactions between disorder and fluctuations. In this work, the dynamic difference between four non-energy transfer and Förster resonance energy transfer (FRET)-assisted random laser systems is investigated based on RSB. It is found that FRET is one of the key factors influencing RSB, and it is demonstrated that RSB in a random laser is not robust. This dynamic difference can be attributed to the different disorders induced by the gain mechanism in different random laser systems. This provides experimental evidence and theoretical support for the classification feasibility of RL with different emission mechanisms employing RSB.

Trapping light within cavities or waveguides in photonic crystals is an effective technology in modern integrated optics. Traditionally, cavities rely on total internal reflection or a photonic bandgap to achieve field confinement. Recent investigations have examined new localized modes that occur at a Dirac frequency that is beyond any complete photonic bandgap. We design Al 2 O 3 dielectric cylinders placed on a triangular lattice in air, and change the central rod size to form a photonic crystal microcavity. It is predicted that waves can be localized at the Dirac frequency in this device without photonic bandgaps or total internal reflections. We perform a theoretical analysis of this new wave localization and verify it experimentally. This work paves the way for exploring localized defect modes at the Dirac point in the visible and infrared bands, with potential applicability to new optical devices.

The discovery of a new type of soliton occurring in periodic systems is reported. This type of nonlinear excitation exists at a Dirac point of a photonic band structure, and features an oscillating tail that damps algebraically. Solitons in periodic systems are localized states traditionally supported by photonic bandgaps. Here, it is found that besides photonic bandgaps, a Dirac point in the band structure of triangular optical lattices can also sustain solitons. Apart from their theoretical impact within the soliton theory, they have many potential uses because such solitons are possible in both Kerr material and photorefractive crystals that possess self-focusing and self-defocusing nonlinearities. The findings enrich the soliton family and provide information for studies of nonlinear waves in many branches of physics.

Tuning transversal resonance modes of localized surface plasmons (LSPs) by the size and the ambient dielectric medium of Ag nanorods is presented. It is found that the resonance wavelength and intensity of the transversal modes of LSPs are closely related to the dimensions of the Ag nanorods embedded in anodic aluminum oxide membranes. The transversal resonance peak exhibits obvious redshifts from 365 to 396 nm with increasing nanorod diameter from 40 to 80 nm, and the resonance intensity remarkably enhances with increasing nanorod diameter. In addition, it is observed that the transversal resonance modes of LSPs in Ag nanorods are strongly sensitive to their surrounding dielectric medium such as water, ethanol, and cetyltrimethylammonium bromide, and the transversal resonance peak distinctly redshifts from 422 to 467 nm when the refractive index of the dielectric medium increases from 1.342 to 1.435. As a result, a refractive index sensitivity of up to 484 nm/RIU can be achieved based on the transversal resonance modes. The transverse resonance modes of LSPs in the Ag nanorods can be used for sensitive quantification of chemical and biological species.

Polarization characteristics of microarrays of silver nanowires embedded in an anodic alumina membrane are theoretically investigated. The microarrays mainly transmit the p-polarized wave, whereas they strongly attenuate the s-polarized wave in the near- and mid-infrared spectral range. We show that the sizes (e.g., diameter, spacing, and ratio of diameter to spacing) of the nanowires strongly affect the optical losses for the polarized waves. It is predicted that large extinction ratios and small insertion losses can be simultaneously achieved by an appropriate choice of the ratio and the diameter. An optimized design of a nanowire grid polarizer at near- and mid-infrared wavelengths is presented.