Tailoring spatiotemporal dynamics of plasmonic vortices

Abstract

Plasmonic vortices confining orbital angular momentums to surface have aroused wide research interest in the last decade. Recent advances of near-field microscopes have enabled the study on the spatiotemporal dynamics of plasmonic vortices, providing a better understanding of optical orbital angular momentums in the evanescent wave regime. However, these works only focused on the objective characterization of plasmonic vortex and have not achieved subjectively tailoring of its spatiotemporal dynamics for specific applications. Herein, it is demonstrated that the plasmonic vortices with the same topological charge can be endowed with distinct spatiotemporal dynamics by simply changing the coupler design. Based on a near-field scanning terahertz microscopy, the surface plasmon fields are directly obtained with ultrahigh spatiotemporal resolution, experimentally exhibiting the generation and evolution divergences during the whole lifetime of plasmonic vortices. The proposed strategy is straightforward and universal, which can be readily applied into visible or infrared frequencies, facilitating the development of plasmonic vortex related researches and applications.

Meta-optics inspired surface plasmon devices

“…As illustrated in Fig. 11(b), Yuan et al demonstrated that different coupler designs can even affect the spatiotemporal dynamics of plasmonic vortices with the same topological charge [299] . Yang et al found unexpected spiral phases in the center of generated plasmonic vortices and demonstrated the existence of deuterogenic plasmonic vortices, as shown in Fig.…”

“…(b) Schematic of the temporal evolution progress of plasmonic vortices with the same topological charge generated by different couplers. Reproduced from an open access reference [299]. (c) Schematic of deuterogenic plasmonic vortex in the center of generated plasmonic vortex with higher topological charge.…”

Freeform Metasurface-Assisted Waveguide Coupler for Guided Wave Polarization Manipulation and Spin–Orbit Angular Momentum Conversion

“…Metasurfaces, with their unprecedented flexibility to manipulate light at the subwavelength scale, have been widely utilized for exotic functional devices. − In addition to free space light manipulation, metasurfaces can also be extensively incorporated into on-chip devices to efficiently modulate guided electromagnetic waves, known as meta-waveguide . Recently, on-chip metalens, polarization rotators, mode converters, and free-space light couplers have been designed based on chip-integrated metasurface. − Moreover, metasurface-assisted waveguide couplers designed based on phase matching conditions and the spin-momentum locking effect can be spin-, mode-, and wavelength-demultiplexing.…”

Characterization of optical forces and torques in polystyrene spheres steered by tightly focused orbital angular momentum beams

“…Since Arthur Ashkin pioneered the development of optical beams that can precisely manipulate micro/nanoparticles [1], many researchers have stabilized the capture of particles by increasing gradient and radiation forces [2][3][4][5]. However, these methods exhibit limitations such as difficulty in maintaining stable capture in the far field.…”