Nanoplasmonic power splitters based on the horizontal nanoplasmonic slot waveguide

Ultracompact power splitters based on the horizontal nanoplasmonic slot waveguide (Cu/SiO2/Si/SiO2/Cu, whose propagation loss is measured to be similar to 0.36 dB/mu m at 1550 nm for waveguide with similar to 47-nm-wide Si core and similar to 26-nm surrounding SiO2) are designed, simulated, and fabricated using the standard complementary metal-oxide-semiconductor technology. The 1 x 2 Y-splitters with the opening angle of 60 degrees, 120 degrees, and 180 degrees are measured to have the excess losses of similar to 1.4, and similar to 3.2 dB, compared with the theoretical values of similar to 1.4, similar to 1.5, and similar to 1.8 dB, respectively. The 1 x 3 cross-splitter delivers normalized output powers of similar to -7.6, similar to -4.2, and similar to -7.2 dB at the left, middle, and right output ports, respectively, compared with the theoretical value of similar to -6.6 dB. Reasons of the discrepancy between the experimental and theoretical results are discussed, and approaches to further reduce the excess loss are then proposed. (C) 2011 American Institute of Physics. [doi:10.1063/1.3615306]