Symmetric tapered dielectric structures in metal have
demonstrated applications such as the nanofocusing of surface
plasmon polaritons, as well as the waveguiding of V-channel
polaritons. Yet the fabrication of smooth-surfaced tapered structure
remains an obstacle to most researchers. We have successfully
developed a handy method to fabricate metal-sandwiched tapered
nanostructures simply with electron beam lithography. Though these
structures are slightly different from conventional symmetric
V-shaped structures, systematic simulations show that similar
functionality of surface plasmon polariton nanofocusing can still be
achieved. When parameters are properly selected,
wavelength-selective nanofocusing of surface plasmon polaritons can
be obtained. 相似文献
A high efficiency and broad bandwidth grating coupler
between a silicon-on-insulator (SOI) nanophotonic waveguide and fibre
is designed and fabricated. Coupling efficiencies of 46\% and
25\% at a wavelength of 1.55~μ m are achieved by simulation
and experiment, respectively. An optical 3~dB bandwidth of 45~nm
from 1530~nm to 1575~nm is also obtained in experiment. Numerical
calculation shows that a tolerance to fabrication error of 10~nm
in etch depth is achievable. The measurement results indicate that
the alignment error of ±2~μ m results in less than 1~dB
additional coupling loss. 相似文献
A compact 64‐channel hybrid demultiplexer based on silicon‐on‐insulator nanowires is proposed and demonstrated experimentally to enable wavelength‐division‐multiplexing and mode‐division‐multiplexing simultaneously in order to realize an ultra‐large capacity on‐chip optical‐interconnect link. The present hybrid demultiplexer consists of a 4‐channel mode multiplexer constructed with cascaded asymmetrical directional‐couplers and two bi‐directional 17 × 17 arrayed‐waveguide gratings (AWGs) with 16 channels. Here each bi‐directional AWG is equivalent as two identical 1 × 16 AWGs. The measured excess loss and the crosstalk for the monolithically integrated 64‐channel hybrid demultiplexer are about ‐5 dB and ‐14 dB, respectively. Better performance can be achieved by minimizing the imperfections (particularly in AWGs) during the fabrication processes.