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CO2-Laser-Inscribed Long Period Fiber Gratings: From Fabrication to Applications

  • Yiping WangEmail author
  • Jun He
Reference work entry

Abstract

This chapter presents a systematic review of long period fiber gratings (LPFGs) inscribed by CO2 laser irradiation. Firstly, various fabrication techniques based on CO2 laser irradiations are introduced that inscribe LPFGs in different types of optical fibers such as conventional glass fibers, solid-core photonic crystal fibers, and air-core photonic bandgap fibers. Secondly, possible mechanisms, including residual stress relaxation, glass structure changes, and physical deformation, of refractive index modulations in the CO2-laser-induced LPFGs are discussed. Asymmetrical mode coupling, resulting from single-side laser irradiation, is analyzed to understand the unique optical properties of the CO2-laser-induced LPFGs. Thirdly, several pre- and posttreatment techniques for enhancing the grating efficiency are described. Fourthly, sensing applications of CO2-laser-induced LPFGs for temperature, strain, bend, torsion, pressure, and biochemical sensors are presented. Finally, communication applications of CO2-laser-induced LPFGs, such as band-rejection filters, gain equalizers, polarizers, couplers, and mode converters, are presented and discussed.

Keywords

Gratings Long period fiber gratings (LPFGs) Optical fiber sensors CO2 laser 

Notes

Acknowledgments

This work was supported by National Natural Science Foundation of China (NSFC) (grant nos. 61425007, 61635007, 61875128, 61377090); Guangdong Natural Science Foundation (grant nos. 2015B010105007, 2014A030308007); Science and Technology Innovation Commission of Shenzhen (grant nos. JCYJ20170412105604705, JCYJ20160427104925452); and Development and Reform Commission of Shenzhen Municipality Foundation.

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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenChina
  2. 2.Guangdong and Hong Kong Joint Research Centre for Optical Fibre SensorsShenzhen UniversityShenzhenChina

Section editors and affiliations

  • John Canning
    • 1
    • 2
    • 3
  • Tuan Guo
    • 4
  1. 1.Faculty of Engineering.University of New South Wales (UNSW)SydneyAustralia
  2. 2.Australian Sensing and Identification Systems Pty. Ltd.SydneyAustralia
  3. 3.School of Computing and CommunicationsUniversity of Technology SydneySydneyAustralia
  4. 4.Institute of Photonics TechnologyJinan UniversityGuangzhouChina

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