High-Transmission-Efficiency 120 <inline-formula> <tex-math notation="TeX">$^{\circ}$</tex-math></inline-formula> Photonic Crystal Waveguide Bend by Using Flexible Structural Defects

Abstract

We numerically studied a high-output-transmission-efficiency low-reflection-loss 120 photonic crystal (PhC) waveguide bend based on a PhC slab with triangular-lattice air holes. The desired high output transmission efficiency was achieved by introducing flexible structural defects into the bend region of the waveguide. Simulation results obtained using a 3-D finite-difference time-domain method indicated that normalized output transmission as high as 94.3% and negligible normalized reflection loss of 0.1% were obtained at the 1550-nm optical wavelength. Furthermore, the normalized output transmission was more than 90% within the entire optical C-band. In addition, sensitivity of the design parameters of the structural defect was studied to understand the tolerance in the fabrication error, while maintaining high output transmission efficiency.

Ultra-Compact Silicon-Based 180-Degree Waveguide Bend Using Digital Metamaterials

“…It is well known that compact bending waveguide is indispensable for routing the data transmission as well as designing PICs flexibly. Great efforts had been made to achieve sharp waveguide-bends by exploiting photonic crystals [1][2][3][4][5][6][7][8][9][10], plasmonics [11][12][13][14][15][16][17][18][19], and micro-ring resonators [20][21][22]. Waveguide bends based on photonic crystals [1][2][3][4][5][6][7][8][9][10] can exhibit high transmission efficiency.…”

“…Great efforts had been made to achieve sharp waveguide-bends by exploiting photonic crystals [1][2][3][4][5][6][7][8][9][10], plasmonics [11][12][13][14][15][16][17][18][19], and micro-ring resonators [20][21][22]. Waveguide bends based on photonic crystals [1][2][3][4][5][6][7][8][9][10] can exhibit high transmission efficiency. However, the footprint of such devices is very large, since photonic crystals exhibit insufficient localization of the electromagnetic waves.…”

“…Multi-dimensional plasmonic waveguide bends [12][13][14][15][16][17][18][19] have been numerically demonstrated. Unfortunately, these devices suffer not only from large absorption losses from metals, but their fabrication itself is challenging since several alternating metal and dielectric layers are required [3][4][5][6][7][8][9][10]. On the other hand, Xu, et. al.…”

Design of adjustable T-shaped and Y-shaped photonic crystal power splitters for TM and TE polarizations

“…In that design, the desired power splitting ratio was achieved by altering the wedge angle at the junction area of the power splitter. Consequently, wedge-type defects were also introduced in the structure of PhC bends [19,20] to improve their transmittance. Tee et al also used this technique to design a cascaded 1 × 3 PhC power splitter based on asymmetric structural defects [21].…”