On the Validity of the Effective Index Method for Long Period Grating Photonic Crystal Fibers

Dhia Khadri, Walid Belhadj, Douha Gamra, Fathi AbdelMalek, Habib Bouchriha

Department of Physics, Jazan University, Jazan, Kingdom of Saudi Arabia.
Ecole Polytechnique de Montreal, Genie Physique, Montreal, Canada.
Faculté des Sciences de Bizerte, Bizerte, Tunisia.
Laboratoire de Physique Quantique et Photonique, Faculte des Sciences de Tunis, Tunis, Tunisia.

DOI: 10.4236/msa.2012.35046                

Abstract

This paper focuses on the investigation of modal characteristics and sensing properties of long period grating photonic crystal fibers (LPG-PCFs). An improved effective index method is employed with an objective to study its limitations for various designs of LPG-PCFs. Results so obtained with the above method are compared with the corresponding values of multiple multipole (MMP) method results which points the range of validity and applicability of the improved effective index method to LPG-PCFs. It is shown that this method is excellent when the surrounding media is assumed to be air. However, it becomes less accurate when the fiber is immersed into a liquid with a refractive index close to that of the cladding.

Keywords

Long Period Gratings Photonic Crystal Fiber (LPG-PCF); Improved Effective Index; MMP; Cladding Modes; Sensor; Sensitivity

Conflicts of Interest

The authors declare no conflicts of interest.

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