The paper reports a novel design for single-polarization single-mode (SPSM) operation at 1310 nm in photonic crystal fibers (PCFs), using a rectangular-lattice PCF with two lines of three central air holes enlarged. The proposed PCF, composed entirely of silica, is modeled by a full-vector finite-element method with anisotropic perfectly matched layers. Simulations show that wideband single-polarization operation can be easily realized with the proposed structure. This wideband SPSM operation, the low confinement losses, and the small effective mode area are the main advantages of the proposed fiber. The influence of varying PCF parameters on the SPSM operation is discussed, and numerical results show that the proposed fiber is a SPSM one with confinement loss less than 0.1 dB/km at wavelengths ranging from 1100 to 1460 nm and effective mode area about 4.3 µm2 at 1310 nm.
In this paper, we have numerically investigated the polarization dependent confinement losses in squeezed photonic crystal fibers (SPCFs) by a full vector finite element with anisotropic perfectly matched layers. Numerical results show that single polarization mode transmission can be realized by maintaining large differential loss between the two polarization states. The effect of the structural parameters has also been explored.
A novel single-polarization single-mode (SPSM) photonic crystal fiber (PCF) is proposed and analyzed through a full-vector finite element method (FEM) with anisotropic perfectly matched layer (PML). Numerical results show that the proposed fiber is a low-loss SPSM-PCF within wavelength range from 1370 to 1610nm, in which only the slow-axis mode is guided and the confinement loss is below 0.1dB/km.
A novel single-mode single-polarization (SMSP) photonic crystal fiber using resonant absorption effect has been put forward and analyzed for the first time, to our knowledge. A full-vector finite element method with perfectly matched layers is employed to investigate the characteristics of the fiber. The numerical results predict that very efficient SMSP operation can be achieved with both high bandwidth and high extinction ratio at low loss penalty. The effects of the fiber structural parameters have been explored, which will provide useful directions for the design and fabrication of the fiber. The research results will be instructive for the realization of new high performance SMSP fibers.
A full-vector finite element method has been used to investigate the high-index-core Bragg fibers including mode field distribution and mode effective index. The influence on the high-index-core Bragg fiber dispersion properties of the low-index-layer filling ratio variations of different rings has been identified. Near-zero flattened dispersion over wide wavelength range was demonstrated in the one-dimensional high-index-core microstructured optical fibers with non-uniform low-index-layer filling ratio in different rings. Both flattened dispersion and low confinement loss can be achieved with finite number of low-index-layer rings.
Three different structures of planar waveguide interleavers are discussed in detail with comparison: Mach-Zehnder interferometer, Mach-Zehnder interferometer with a ring resonator, and AWG(arrayed waveguide grating) . Further, we demonstrated a 1:4 AWG-based interleaver with 50GHz channel spacing, flatten passband and low channel crosstalk can be achieved by proper design.