The near-field radiation pattern of a long thin slit (with a width much smaller than the excitation wavelength) in a uniform aluminum surface was measured and modeled by numerical computation. In particular, the interplay between the incident light polarization and the slit width is found to play an essential role in the near-field profile on the back side of the nanoslits. Two-dimensional finite-difference time-domain computer simulations were performed to calculate the near-field intensity profile for different slit widths and metal thicknesses. This method will allow the optimization of three-dimensional near-field radiation patterns for a variety of near-field molecular scanning schemes.
© 2004 Optical Society of America
Cheng Hung Wei, Pei Hsi Tsao, Wunshain Fann, Pei-Kuen Wei, Jonas O. Tegenfeldt, and Robert H. Austin, "Polarization dependence of light intensity distribution near a nanometric aluminum slit," J. Opt. Soc. Am. B 21, 1005-1012 (2004)