Polarization dependence of asymmetric off-resonance long period fiber gratings

Asymmetric transverse-load characteristics and polarization dependence of long-period fiber gratings written by a focused CO(2) laser.

Asymmetric transverse-load characteristics and the polarization dependence of long-period fiber gratings (LPFGs) written by high-frequency CO(2) laser pulses are investigated in detail. It is demonstrated that the resonant wavelength is dependent on the direction of the applied force and on the polarization state of the input light; however, the coupling strength is independent of these paramet...

Polarization-dependent loss and birefringence in long-period fiber gratings.

Widely used descriptions and relationships for birefringence and polarization-dependent loss (PDL), developed primarily for ultraviolet-induced long-period fiber gratings (LPFGs) written in optical fiber, can be invalid for other types of LPFG. The understanding of PDL is expanded to include LPFGs with birefringence in the core only, in the cladding only, and in both the core and the cladding. ...

Polarization-insensitive multi-wavelength switching based on polarization-selective long-period fiber gratings.

Novel multi-wavelength switching filters based on cascaded long-period fiber gratings and polarization-maintaining fiber in a Sagnac loop configuration are proposed and experimentally demonstrated. The rapid wavelength switching is achieved by an electro-optic polarization controller. The device is independent of the polarization state of the input light due to the bi-directional polarization c...

Novel fiber design for broadband long period gratings

We report a novel fiber design for obtaining long period gratings (LPGs) having a broad transmission spectrum. These gratings are based on guided to guided mode coupling in a staircase profile fiber. Numerical simulations predict 20 dB bandwidths as high as 100 nm and an estimated insertion loss of less than 1 dB. Such broadband LPGs are expected to find applications in many all fiber components.

Long Period Fibre Gratings