Ultrafast All‐Optical Polarization Switching Based on Composite Metasurfaces with Gratings and an Epsilon‐Near‐Zero Film

Abstract

Active control of light polarization is necessary for the development of laser physics, optical communications, and also the molecular dynamics. Conventional polarization control methods suffer from low speed, and the existing all‐optical switching based on nonlinear materials solely has a lot of conducting restrictions, impeding its practical utilizations. Herein, an all‐optical polarization switching in the near‐IR range, composed of the plasmonic gratings deposited on an indium tin oxide (ITO) film with epsilon‐near‐zero response, is realized. A sub‐1 ps response speed and the 19° rotation of the polarization ellipse are determined with the excitation power of 1.37 GW cm−2. The device is demonstrated to output the varied signal with tuning the incident polarization and intensity in a spectral range from 1200 to 1500 nm. The ultrafast processing speed, broadband, and diverse tunability ensure the designed device a promising and necessary element for practically integrating into the next‐generation signal‐processing systems with high performance and large capacity.

Polarization‐Multiplexed Silicon Metasurfaces for Multi‐Channel Visible Light Modulation

“…Recently, plenty of functional metasurface devices have been reported, including metagratings, [5][6][7][8] high quality factor devices, [9,10] spontaneous emission control, [11][12][13] magnetic mirrors, [14] cloaking, [15][16][17][18][19][20] optical vortex beam generators, [21][22][23][24][25] and so on. [26][27][28][29][30][31][32][33][34][35][36][37][38][39] In order to achieve the desired functionality with high efficiency, the materials used to fabricate metasurfaces should not only strongly interact with light but also have low intrinsic losses. Metal-based plasmonic metasurfaces [40][41][42] and dielectric-based Mie metasurfaces [43][44][45] are the predominantly two class strategies for enhancing the light and matter interactions with resonant subwavelength structures.…”

“…Recently, plenty of functional metasurface devices have been reported, including metagratings, [ 5–8 ] high quality factor devices, [ 9,10 ] spontaneous emission control, [ 11–13 ] magnetic mirrors, [ 14 ] cloaking, [ 15–20 ] optical vortex beam generators, [ 21–25 ] and so on. [ 26–39 ]…”

Optimization of Epsilon-Near-Zero Multilayers for Near-Perfect Light Absorption Using an Enhanced Genetic Algorithm

“…ENZ photonics has attracted extensive attention in recent years, which is considered as a new platform for integrating photonic and nanophotonic devices [9]- [12]. In combination with ENZ materials, a variety of optical metamaterials and devices with different functions have been designed based on hollow waveguide structures [13], [14], grating structures [10], [15], [16], multilayer structures [17], [18] and complex hybrid structures [19], [20].…”

“…A metal-dielectric pair is taken as a period and its optical absorption performance is improved by adjusting the total thickness or the number of multilayer periods. The absorption performance can also be enhanced by adding grating structure on the metasurface of the multilayer [10]. However, increasing the total thickness of the multilayer increases the volume and the production cost, which limits the integration level; and increasing the number of multilayer periods and introducing gratings increase the manufacturing difficulties.…”

All-optical polarization tuning based on an intensity-dependent nonlinear metasurface

“…Lately, typical epsilon-near-zero (ENZ) materials, such as indium tin oxide (ITO) and indium-doped cadmium oxide, were utilized to achieve a dynamic polarization rotation. However, the maximum phase change was very limited and the polarization was merely switched from linear polarization to elliptical polarization [10,11].…”