Mechanically-Induced Long-Period Fiber Gratings Using Laminated Plates.

Ismael Torres-Gómez,Daniel E Ceballos-Herrera,Karla M Salas-Alcantara

doi:10.3390/s20092582

Abstract

This work presents a formation method of mechanically-induced long-period fiber gratings using laminated plates. The mechanically-induced long-period fiber grating is temporarily inscribed by compressing the optical fiber between a flat plate and the proposed laminated plate. In turn, the new laminated plate consists of a parallel assembling of single-edged utility blades. We present the experimental characterization of mechanically-induced long-period fiber gratings while employing three laminated plates with a period of 480 ± 20 µm and low duty cycles. These mechanically-induced long-period fiber gratings display a leading rejection band (>15 dB) with a couple of shallow rejection bands (<2 dB) in the range of 1100–1700 nm. This spectral behavior is due to the new mechanical fabrication process that is based on laminated plates that we have proposed, which consists of piling multiple blades with trapezoidal edges that are polished with different levels to obtain different duty-cycles. With the proposed method, we can obtain values of duty-cycles around 10%, much lower than those obtained using traditional methods. Additionally, with this new method, the required mechanical pressure to form the grating is remarkably reduced, which minimizes the probability of the optical fiber failure in the mechanically-induced long-period fiber gratings (MI-LPFGs). Moreover, the proposed mechanically-induced long-period fiber gratings with a single rejection band open the feasibility to implement coarse wavelength division multiplexing systems that are based on long-period fiber gratings.

Highlights

IntroductionLong-period fiber gratings (LPFGs) are wavelength-selective components that allow the energy coupling from the fundamental core mode to the co-propagating higher-order cladding modes
Long-period fiber gratings (LPFGs) are wavelength-selective components that allow the energy coupling from the fundamental core mode to the co-propagating higher-order cladding modes.This modal coupling results in multi rejection bands in the optical transmission, in which their resonant central wavelengths depend on the phase-matching condition [1]
We experimentally analyze the influence of the average duty cycle (ADC) on the leading rejection band in the MI-LPFGs

Summary

Introduction

Long-period fiber gratings (LPFGs) are wavelength-selective components that allow the energy coupling from the fundamental core mode to the co-propagating higher-order cladding modes. This modal coupling results in multi rejection bands in the optical transmission, in which their resonant central wavelengths depend on the phase-matching condition [1]. Since the end of the 90s, to date, many techniques have been reported in the LPFGs inscription, such as UV, CO2 , femtosecond irradiation, electric arc, and mechanically-induced between other methods [1,5,6,7,8]. Other methods have been proposed using the attractive LPFGs inscription process [13,14,15]

Methods

Results

Conclusion