Manipulation for Superposition of Orbital Angular Momentum States in Surface Plasmon Polaritons

Abstract

states can generate structured spatial light fields via the comprehensive manipulations of the helical phase, polarization, and propagation of the light. Intuitively, the equal-weighted superposition of OAM states with TCs of opposite signs may generate spatial modes of petal-like intensity with nonzero or zero global OAMs, and superpositions of higher-order OAMs may produce wheel-like modes with azimuthal variations of intensity in high dimensions. A variety of methods or devices have been developed to enable the superposition of OAMs. These include liquid crystal q-plates, [1][2][3] spatial light modulators, [4,5] crystal prism pairs, [6] microscopic ring resonators, [7,8] and other optical elements. [9][10][11] Moreover, the progress in OAM superposition has brought about many important applications in classical physics and quantum sciences. Classical applications include particle trapping, [12] optical communications, [13,14] and relativistic laser-matter interactions. [15,16] In the quantum field, important advancements have been made in quantum communications, [17][18][19] quantum information processing, [20,21] and quantum calculations. [22,23] The potential to miniaturize superposed spatial modes of OAM to nanoscale is promising for the implementation of integrated on-chip devices. Metasurfaces consisting of monolayers of subwavelength metallic/dielectric structures have become an efficient way to manipulate light at the subwavelength scale. In recent several years, the study of metasurfaces has attracted great interest in areas as phase-controlled, [24] broadband vectorial holograms, [25] broadband achromatic metalenses, [26] and the coherent control of plasmonic spin-Hall effects. [27] The development of metasurfaces for the manipulation of OAM states has also been studied extensively. [28][29][30][31][32][33][34][35] In the past year, significant progress has been made in achieving arbitrarily controlled OAM superposition states via metasurface engineering. Devlin et al. have proposed the metasurface J-plate to realize the superposition of independent OAM states and to convert SAMs into total angular momentum states. [36] Using a reflective plasmonic metasurface, Yue et al. demonstrated various OAM superpositions in multiple channels by changing the polarization of the illumination. [37,38] By designing a nonlinear plasmonic metasurface for the simultaneous control of the OAM and SAM, Li et al. achieved the OAM superposition of the modes of the second Superposition of orbital angular momentum (OAM) states and the structured intensity are providing new approaches for manipulating optical information and light-matter interactions. While superposition of OAMs in free space has been well studied, further extensions to surface plasmon polariton (SPP) confined in near-field would be crucial for miniaturing and integrating platforms. Here, the plasmonic metasurfaces consisting of rotated nanoslits arranged in a segmented spiral are proposed to realize the superposition of two SPP OAM states. The nanoslit rota...

Design of Metasurface with Nanoslits on Elliptical Curves for Generation of Dual-Channel Vector Beams

“…To generate the VBs, researchers have proposed various methods over the last decade by using different traditional optical systems such as Michelson [11], Mach-Zehnder [12], Sagnac interferometers [13], and elements such as spatial light modulators [14], wave plates [15], Daman gratings [16], q-plates [17]. The generated versatile VBs include first-order and high-order VBs [18,19], vector beam arrays [20], high-order Nanomaterials 2021, 11, 3024 2 of 16 Poincaré beams [2], etc. However, these bulky optical systems often contain numerous optical elements and need complicated operations, which hinders the applications of VBs for miniaturized integrations.…”

Polarization‐Independent Wavefront Manipulation of Surface Plasmons with Plasmonic Metasurfaces

“…[1][2][3] One of the meaningful applications have been demonstrated, including directional launching, [8][9][10] Airy beams, [4,[11][12][13][14] near-field focusing, [15][16][17][18] cosine-Gauss beam, [19][20][21][22] and vortex beams. [23][24][25][26] However, most of these configurations are polarization-sensitive since they can only convert spatial light waves into SPs under specific incident polarization state. A minority of design strategies can operate under arbitrary polarization states, but only have phase modulation.…”

Polarization-Independent Metasurface Lens Based on Binary Phase Fresnel Zone Plate

“…In addition, the wavefront of the transmitted wave can be further manipulated in the desired manner by designing the arrangement of the antennas. Various ultrathin metasurface devices, such as lenses [ 4 , 9 , 12 , 13 , 14 , 15 ], vortex phase plates [ 16 , 17 , 18 , 19 , 20 , 21 , 22 ], holographic plates [ 6 , 23 , 24 , 25 , 26 ], and refraction deflectors [ 1 , 27 , 28 ], have been demonstrated. Lenses are fundamental optical components and play important roles in practical applications.…”