This paper reports that Goos-Hǎnchen （GH） shifts occurring on a symmetrical metal-cladding waveguide are experimentally identified. It was found that there exists a critical thickness of the upper metal layer, hcr,...This paper reports that Goos-Hǎnchen （GH） shifts occurring on a symmetrical metal-cladding waveguide are experimentally identified. It was found that there exists a critical thickness of the upper metal layer, hcr, above which negative shift is observed and, reversely, positive shift occurs. Both positive and negative GH shifts near the critical thickness do not vary dramatically and can achieve a maximum on the submillimeter scale, which is different from simulated results using the stationary-phase method. It also shows that this critical thickness, hcr, can be obtained at the position for zero reflectivity by setting the intrinsic damping to be the same as the radiative damping. The GH effects observed near the critical thickness are produced by extreme distortion of the reflected beam profiles, which limits the amplitude of the GH shift and, further, the sensitivity of the GH optical sensor based on the symmetrical metal-cladding waveguide.展开更多
We report on the first demonstration of a proof-of-principle optical fiber‘meta-tip’,which integrates a phase-gradient plasmonic metasurface on the fiber tip.For illustration and validation purposes,we present numer...We report on the first demonstration of a proof-of-principle optical fiber‘meta-tip’,which integrates a phase-gradient plasmonic metasurface on the fiber tip.For illustration and validation purposes,we present numerical and experimental results pertaining to various prototypes implementing generalized forms of the Snell’s transmission/reflection laws at near-infrared wavelengths.In particular,we demonstrate several examples of beam steering and coupling with surface waves,in fairly good agreement with theory.Our results constitute a first step toward the integration of unprecedented(metasurface-enabled)light-manipulation capabilities in optical-fiber technology.By further enriching the emergent‘lab-on-fiber’framework,this may pave the way for the widespread diffusion of optical metasurfaces in real-world applications to communications,signal processing,imaging and sensing.展开更多
基金Project supported by the Research Fund for Selecting and Training Excellent Young Teachers in Universities of Shanghai, Shanghai Municipal Education Commission (Grant No slg08006)"Chen Guang" project of Shanghai Municipal Education Commission and Shanghai Education Development Foundation (Grant No 09CG49)+2 种基金Dawn Project of Education Committee of Shanghai and Shanghai Education Development Foundation (Grant No 08SG48)Innovation Program of Shanghai Municipal Education Commission (Grant No 09YZ221)the Program from Shanghai Committee of Science and Technology, China (Grant Nos 07DZ22026 and 08ZR1415400)
文摘This paper reports that Goos-Hǎnchen （GH） shifts occurring on a symmetrical metal-cladding waveguide are experimentally identified. It was found that there exists a critical thickness of the upper metal layer, hcr, above which negative shift is observed and, reversely, positive shift occurs. Both positive and negative GH shifts near the critical thickness do not vary dramatically and can achieve a maximum on the submillimeter scale, which is different from simulated results using the stationary-phase method. It also shows that this critical thickness, hcr, can be obtained at the position for zero reflectivity by setting the intrinsic damping to be the same as the radiative damping. The GH effects observed near the critical thickness are produced by extreme distortion of the reflected beam profiles, which limits the amplitude of the GH shift and, further, the sensitivity of the GH optical sensor based on the symmetrical metal-cladding waveguide.
文摘We report on the first demonstration of a proof-of-principle optical fiber‘meta-tip’,which integrates a phase-gradient plasmonic metasurface on the fiber tip.For illustration and validation purposes,we present numerical and experimental results pertaining to various prototypes implementing generalized forms of the Snell’s transmission/reflection laws at near-infrared wavelengths.In particular,we demonstrate several examples of beam steering and coupling with surface waves,in fairly good agreement with theory.Our results constitute a first step toward the integration of unprecedented(metasurface-enabled)light-manipulation capabilities in optical-fiber technology.By further enriching the emergent‘lab-on-fiber’framework,this may pave the way for the widespread diffusion of optical metasurfaces in real-world applications to communications,signal processing,imaging and sensing.
