摘要
A super-focusing device composed of a focusing objective and a hyperlens is proposed to focus an incident plane wave into the deep subwavelength dimension. In the device, the objective converts the incident plane wave into a convergent one. The half cylindrical hyperlens can support high wave vector k modes propagating towards its core. So the convergent wave can be focused into an ultrasmall spot beyond the diffraction limit. The layout is proposed for the super-focusing device and its characteristics are investigated theoretically. Numerical simulations verify that the focused beams are confined in a spot with a diameter of 16.3 nm in the focal plane of the focusing objective with a numerical aperture of 0.6, which corresponds to a super-resolution spot of λ0/23 (λ0 is the wavelength in vacuum). The simulations confirm the effectiveness of the proposed device.
A super-focusing device composed of a focusing objective and a hyperlens is proposed to focus an incident plane wave into the deep subwavelength dimension. In the device, the objective converts the incident plane wave into a convergent one. The half cylindrical hyperlens can support high wave vector k modes propagating towards its core. So the convergent wave can be focused into an ultrasmall spot beyond the diffraction limit. The layout is proposed for the super-focusing device and its characteristics are investigated theoretically. Numerical simulations verify that the focused beams are confined in a spot with a diameter of 16.3 nm in the focal plane of the focusing objective with a numerical aperture of 0.6, which corresponds to a super-resolution spot of λ0/23 (λ0 is the wavelength in vacuum). The simulations confirm the effectiveness of the proposed device.
基金
supported by the National Natural Science Foundation of China(Grant No.10904118)
the Natural Science Foundation of Hubei Province,China(Grant No.2009CDB211)
the Fundamental Research Funds for the Central Universities of China