Quadrate hole array is explored to study the influence of unsymmetrical
periodicity on extraordinary optical transmission through periodic arrays of
subwavelength holes. It is found that the transmission efficiency of light and
the ratio between transmission efficiencies of horizontal and vertical
polarized light can be continuously tuned by rotating the quadrate hole array.
We can calculate out the transmission spectra (including the heights and
locations of peaks) for any rotation angle θ with a simple theoretical
model.Comment: 6 pages, 5 figure