Spectrally investigated optimization for high optical transmission of the C-shaped nano apertures

Due to the maturity of current laser technology, the limitation of empirical wavelengths of lasers useful for optical microlithography makes spectrally investigated optimization very important for the design of C-shaped nano apertures; in order to achieve high optical transmission as well as tight focusing, the resonant transmission of nano apertures depends on the incident light's wavelength. The optically propagating transmission through the nano aperture, determined by the effects of the propagating field and evanescent field, is also important in order to achieve deep patterning. High power throughput and decaying behaviors of propagating light through nano apertures depend on their resonance condition which is affected by geometric parameters and material properties as well as the wavelength of incident light. In this report, we analyze the spectral properties of resonant transmission of light through a C-shaped nano aperture in a metal film using a finite-difference time-domain (FDTD) simulation. These simulations may be helpful for the design of C-shaped nano apertures for high power throughput with tight focusing. Furthermore, we show that power dissipation of propagating light through the C-shaped nano aperture depends on metals.