Polarization-controllable perfect vortex beam by a dielectric metasurface

Abstract

A perfect vortex beam has been attracting tremendous attention due to the fact that its ring radius is independent of the topological charge. Taking advantage of the superposition principle of phase in Fourier space, we proposed to generate perfect vortex beam using propagation-phase-based dielectric metasurface, which exhibits production efficiency larger than 83.5%. Due to the sensitivity of propagation phase to the polarization of incident beam, two sets of phase profiles can be imposed on a single dielectric metasurface, enabling the simultaneous generation of dual perfect vortex beams. Based on this property, convenient control to the radius and/or topological charge of perfect vortex beam is achieved by switching the incident polarization between two orthogonal polarizations, without redesigning metasurface or changing optical path. What’s more important, the crosstalk of these two channels is low, less than 4%. Thus, the propagation-phase method of producing perfect vortex beam will find significant applications in optical communication, particle trapping, particle manipulation and holographic display.

Dual-Wavelength Polarization-Dependent Bifocal Metalens for Achromatic Optical Imaging Based on Holographic Principle

“…Composed of subwavelength nanostructures, optical metasurfaces feature the exotic capability to arbitrarily modulate the light properties, such as the phase, amplitude and polarization at the nanoscale [1][2][3][4][5]. Due to their superiority in wavefront modulation, a plethora of planer optical devices have been extensively investigated, including metahologram [6][7][8], beam steering [9], vortex generators and detectors [10][11][12] and polarization analysis [13].…”

Generation and Superposition of Perfect Vortex Beams in Terahertz Region via Single-Layer All-Dielectric Metasurface

“…However, the transmission of the incident beam through the metasurface is deficient due to the large ohmic absorption caused by Au nanostructures. In 2021, Xie et al designed a polarization-controllable dielectric metasurface in NIR to generate two different PVBs by switching the incident polarization utilizing propagation phase theory [ 39 ]. Compared to metal metasurface, dielectric metasurface displays higher work efficiency.…”

Terahertz Near‐Field Vortex Beams with Variable Intensity Profiles Based on Geometric Metasurfaces

“…Recent works regarding geometric metasurface such as generalized Snell's law [14][15][16], holograms [17][18][19][20][21][22][23][24], metalens [25][26][27][28][29][30][31][32][33][34], spin Hall effect [35][36][37][38], polarization convertors [39][40][41][42][43], and nonlinear photonics [44][45][46][47] have sufficiently proven its outstanding capabilities in EM wave manipulation. Moreover, the generations of vortex beams [48][49][50][51][52], vector vortex beams [53,54] and perfect vortex beams [55][56][57] have been demonstrated using geometric metasurface approach. Recently, generalized vortex beams, in which the corresponding intensity profiles have C N -fold discrete rotational symmetry instead of continuous rotational symmetry for conventional vortices, have been demonstrated in free space, because of unique properties in intensity and phase ...…”