Photonics Research, 2018, 6 (1): 01000054, Published Online: Jul. 10, 2018
Mode selection and dispersion engineering in Bragg-like slot photonic crystal waveguides for hybrid light–matter interactions Download: 690次
Figures & Tables
Fig. 1. SOI SPhCW covered by a cladding material of n clad index. (a) Geometry with the parameters shown: n Si = 3.48 , n SiO 2 = 1.44 , n clad = 1.52 , r 1 = 120 nm , r = 105 nm (radius of all holes outside the two first rows); (b) influence of the slowing-down factor (n G ) on the confinement properties of SPhCW designed for the integration of materials of index ∼ 1.5 : dielectric energy confinement (η clad ) of the W1-like and true-slot modes; (c) and (d) dispersion diagrams for W S = 80 nm , W S = 200 nm , respectively. Additionally, insets give the real-space E y -field component distributions of the three modes at k = 0.5 × 2 π c / a in linear scale. Fields are normalized to carry a unitary mode dielectric energy.
Fig. 2. Dielectric energy confinement in the low-index material (η clad ) of silicon SPhCWs studied through the SOI SPhCW configuration described in Fig. 1 at the edge of the Brillouin zone: (a) true slot mode and (b) W1-like mode.
Fig. 3. Bragg-like corrugated SPhCWs. (a) Description of the waveguide geometry; (b)–(d) dispersion diagrams obtained for a 50/150 nm corrugated slot in which wide parts are aligned with the two nearest neighboring holes (d x = 0 ) for r 1 = 110 , 125, and 140 nm, respectively (all other parameters being identical to the one described in Section 1, including r 2 = 105 nm ).
Fig. 4. Strong influence of the r 2 parameter on the frequency splitting between the two even-mode symmetry slot modes: (a) dispersion diagram obtained for r 1 = 140 nm and r 2 = 95 nm (see Section 1 for a complete description of all other parameters; the two arrows are an identification of the two studied modes); (b) wavelength splitting between the true-slot and W1-like modes as a function of r 2 .
Fig. 5. Adjustment of the dispersive properties of the corrugated SPhCW by the r 2 parameter: (a) group index and GVD proprieties (β 2 ) for the r 2 = 115 nm configuration; (b) evolution of the SPhCW “flat band slow light” normalized delay product of the true slot mode as a function of the diameter of the second row of holes (r 2 ).
Samuel Serna, Weiwei Zhang, Thi Hong Cam Hoang, Carlos Alonso-Ramos, Delphine Marris-Morini, Laurent Vivien, Eric Cassan. Mode selection and dispersion engineering in Bragg-like slot photonic crystal waveguides for hybrid light–matter interactions[J]. Photonics Research, 2018, 6(1): 01000054.