1,721,302 research outputs found
Modal selective tuning in a photonic crystal cavity
No full textWe present a way to selectively tune the properties of the degenerated modes confined in a single point defect two-dimensional photonic crystal cavity based on a triangular lattice of air holes. We investigate the dependence of the modal properties of the resonator on the position of the first neighbor holes, showing that it is possible to finely tune the resonant frequency of only one of these two modes and to increase the quality factor of the mode that has no frequency shift. This is achieved by controlling the wavevector components inside the cavity. This approach is a viable strategy for the development and the optimization of several innovative devices based on bi-modal cavity arrays, such as arrays of integrated optical filters and optical read-out sections for biosensing applications
Transverse resonance circuit modeling and hertzian potential formulation for integrated optical waveguides
No full textIn this work we present a new efficient numerical simulator based on the concepts of transverse resonance and electromagnetic Hertzian potentials. The method includes the transverse resonance circuit modelling (TRCM) well suited with scalar time-domain Hertzian potential modelling (HPM). The transverse circuit provides the effective refractive indices related to the guided modes of an optical waveguide. The simultaneous implementation of the TRCM and HPM approaches provides an accurate time domain electromagnetic field solution for two-dimensional and three-dimensional optical waveguides
Anisotropic effects in circular photonic crystals
No full textWe analyze accurately in this work the form birefringence effects in circular photonic crystals at optical frequencies. As in dielectric multilayered structures which behave as negative uniaxial crystals the dielectric concentric circular patterns admit two preferred propagation directions defined by an extraordinary and an ordinary refractive index representing two field polarizations. The model is obtained through the geometrical synthesis of the wave front propagation inside the anisotropic structure. The model is applied to Si/SiO2 dielectric rings photonic crystal which behaves as a Bragg reflector, and to GaAs photonic crystal resonator with cylindrical air holes. The theory is validated by analytical, numerical and experimental results, and can be extended to circular microwave photonic crystals
- …
