We studied a two-dimensional square lattice of Si nanopillars (SQLN) perspe
ctive for applications in waveguides. Reflection spectra of SQLN with the p
eriod of 270 nm were studied for different surrounding media, namely air an
d water. SQLN is shown to display photonic band gap (PBG) behavior in the v
isible-infrared spectral range. The energy positions and widths of the expe
rimentally observed reflection bands are found to be in agreement with calc
ulated PBG. (C) 1999 American Institute of Physics. [S0003-6951(99)02947-2]
.