Extraordinary transmission in the ultraviolet range from subwavelength slits on semiconductors

In this paper, we describe a way to achieve the extraordinary transmission regime well into the UV range using subwavelength slits carved on semiconductor substrates. Unlike metals, the dielectric permittivity of typical semiconductors like GaAs or GaP is negative beginning in the extreme UV range (lambda <= 270 nm) and is characterized by large absorption. We show that the metallike response of bulk semiconductors exhibits surface plasmon waves that lead to extraordinary transmission in the UV and soft x-ray ranges, in spite of the large absorption. The importance of realistic material response versus perfect conductors is also discussed. We show that the use of perfect conductor boundary conditions can lead to field amplitudes that may be underestimated by several orders of magnitudes. These findings may be important in high resolution photolithography, near-field optical devices, and ultrahigh density optical storage in wavelength ranges, where it may not be possible to utilize more traditional plasmonic materials like noble metals. (C) 2010 American Institute of Physics. [doi:10.1063/1.3318460]