摘要
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.
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.
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)
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)