  Plasmonic detectors have the potential to provide a method of rapid
spectroscopy without the need of moving mirrors or gratings. Previous
measurements have demonstrated frequency tunable detection based on plasmonic
excitations, however these devices were either small area, polarization
dependent and/or required e-beam lithography. We demonstrate that large area
high sensitivity THz plasmonic detection can be achieved using self-assembly
nanosphere lithography. We achieve a submicron feature size grid covering a
detector area of 4 mm^2. Measurements at 80 K show a large transmission change
of 25% and a blue shift with decreasing aperture size due to coupling of disk
lattice. The resonant frequencies of our device are function of radius, not
periodicity. We also confirmed a magneto plasmon dispersion of the device. In
conclusion we find that fabrication of self-assembled grids is a rapid and
reliable method for plasmonic devices in the terahertz range.
