A high-performance absorbing boundary condition is newly del eloped for the
reduction of spurious reflections in photonic crystal (PC) waveguide simul
ations. The PC waveguide is terminated with a perfectly matched layer (PML)
in which the original PC structure remains as is. This PC-based PML works
well, compared to a conventional PML, which acts as a homogeneous absorbing
medium, simulating a semi-infinite free space and to a distributed-Bragg-r
eflector waveguide, which was recently developed to reduce reflections from
PC waveguide ends, improving a wavenumber matching condition for PC wavegu
ide modes.