Fiber Bragg grating strain modulation based on nonlinear string transverse-force amplifier

Fiber Bragg grating strain modulation based on nonlinear string transverse-force amplifier.

The only effective method of fiber Bragg grating (FBG) strain modulation has been by changing the distance between its two fixed ends. We demonstrate an alternative that is more sensitive to force based on the nonlinear amplification relationship between a transverse force applied to a stretched string and its induced axial force. It may improve the sensitivity and size of an FBG force sensor, ...

Experimental demonstration of nonlinear pulse propagation in a fiber Bragg grating written in a fiber amplifier.

We study experimentally nonlinear propagation of sub-nanosecond optical pulses in a fiber Bragg grating written in a Ytterbium-doped fiber amplifier (YD-FBG). The magnitude and the sign of group velocity dispersion (GVD) in YD-FBG can be controlled by adjusting the fiber tension. In the case of anomalous GVD, pulse breakup was observed due to modulation instability. However, for the same input ...

A Highly-sensitive Fiber Bragg Grating Transverse Strain Sensor Using Micro-structure Fibers

Unique Solution of Short Pulse Propagation in Nonlinear Fiber Bragg Grating

In this study, a new numerical method is introduced to obtain the exact shape of output pulse in the chalcogenide fiber Bragg grating (FBG). A Gaussian pulse shape with 173 ps width is used as an input pulse for lunching to a 6.6 mm nonlinear FBG. Because of bistable and hysteresis nature of nonlinear FBG the time sequence of each portion of pulse is affected the shape of output pulse. So we di...

Optimization of Bistability in Nonlinear Chalcogenide Fiber Bragg Grating for All Optical Switch and Memory Applications

We solve the coupled mode equations governing the chalcogenide nonlinear fiber Bragg gratings (FBGs) numerically, and obtain the bistability characteristics. The characteristics of the chalcogenide nonlinear FBGs such as: switching threshold intensity, bistability interval and on-off switching ratio are studied. The effects of FBG length and its third order nonlinear refractive index on FBG cha...