Spectra of dual overwritten fiber Bragg grating

• Published in: Optics communications Vol. 188; no. 1; pp. 31 - 39
• Main Authors: Bao, Jilong, Zhang, Xianmin, Chen, Kangsheng, Zhou, Wen
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.02.2001; Elsevier Science
• Subjects: Applied sciences; Circuit properties; Coupled-mode theory; Dual overwritten grating; Electric, optical and optoelectronic circuits; Electronics; Exact sciences and technology; Fiber Bragg grating; Integrated optics. Optical fibers and wave guides; Optical and optoelectronic circuits; Other fiber-optical devices; Dual overwritten grating; Fiber Bragg grating; Coupled-mode theory; Diffraction grating; Phase grating; Ultraviolet radiation; Reflection spectrum; Coupled mode analysis; Bragg grating; Photoinduced effect; Numerical simulation; Optical fiber
• ISSN: 0030-4018; 1873-0310
• DOI: 10.1016/S0030-4018(00)01097-X

The perturbation to the refractive index induced by dual overwritten fiber Bragg grating (FBG) is analyzed, and the coupled-mode equations are obtained. The spectral characteristics that can be achieved in dual overwritten fiber gratings are investigated by numerical simulation. It is found that the spectral characteristics are affected significantly by period difference ΔΛ, primary phase difference Δφ and grating length L. Moreover, multiwavelength reflection and strong second harmonics will occur in dual written FBG when the nonlinear UV-induced index perturbation exists, which is very useful for multichannel wavelength-division multiplexing. The results concluded in this paper are conducive to the fabrication and applications of dual overwritten FBGs.