Large Goos-Hanchen displacement of evanescent light beam in near-field enhanced configuration - art. no. 683103

We report that the transmitted evanescent light beam under total reflection will experience a lateral displacement similarly to that of the reflected beam, called Goos-Hanchen (GH) effect. By a dielectric thin film coated onto the dielectric surface, which is usually considered as the near-field enhanced configuration in atom optics, we indicate that the displacement of the transmitted evanescent beam can be greatly enhanced to several tens of wavelengths at transmission resonance under total internal reflection. Numerical simulations have been performed and it is shown that the transmitted evanescent beam maintains well the shape of the incident beam when the thickness of the thin film is required to be of the order of wavelength. Further, it is demonstrated that the stationary-phase approach is also applicable to transmitted evanescent beam and the GH displacement of the transmitted beam is just half the GH displacement of the reflected beam. The discussions presented here may arouse interest in atom optics and near-field microscope.