Numerical Study of a High-Resolution Far-Field Scanning Optical Microscope via a Surface Plasmon-Modulated Light Source

In this paper, we analyze light transmission through a single subwavelength slit surrounded by periodic grooves in layered films consisting of Au and dielectric material. A subwavelength grating is scanned numerically by the finite difference time domain method in two dimensions. The results show that the transmission field can be confined to a spot with subwavelength width in the far field and can be useful in the application of a high-resolution far-field scanning optical microscope