Slow-light Effect in Symmetry-reduced Non-defect Photonic Crystals

In this study, a two-dimensional low-symmetric photonic crystal (PC) configuration with elliptical geometry is presented and its slow-light (SL) effect investigated. Reducing the symmetry in PC unit cell provides slow modes at higher transverse electric bands. The calculated group index corresponding normalized bandwidth equal to {ng, BW}={63.56, 0.0065}. That corresponds value of figure merit (FOM)=0.4344 defined by product average bandwidth, FOM=〈ng〉BW, which comparable values available literature. Tracing whole edges Brillouin zone, strongly excited SL are observed only along Γ-X but not Γ-X’ or Γ-M. condition allows for design waveguides finite thicknesses expense lowering value. still obtained proposed PCs having thicknesses, numerically proved via finite-difference time-domain methods. It important note that non-dispersive Bloch exist through non-zero k-vector components zone. Hence, such defect-free (without either point- line- defect) may have great potential use compact devices as optical switching biochemical sensing applications.