Long-period fibre grating fabrication with focused CO2 laser pulses

Davis, Donald D.; Gaylord, Thomas K.; Glytsis, Elias N.; Kosinski, S. G.; Mettler, Stephen C.; Vengsarkar, Ashish M.

doi:10.1049/el:19980239

Cited by 298 publications

(169 citation statements)

References 10 publications

Supporting

Mentioning

160

Contrasting

Unclassified

Order By: Relevance

“…where ⌬n residual is the initial refractive index perturbation induced by the residual stress relaxation resulting from the high local temperature, which is similar to the case of the CO 2 -laser-induced LPFGs without periodic grooves; 2,3 ⌬n groove is the initial refractive index perturbation induced by the periodic grooves on the fiber, which is similar to ⌬n corrugated in the corrugated LPFGs fabricated by hydrofluoric acid etching; 4 ⌬n stretch is the refractive index perturbation induced by the stretching force and can be expressed as…”

mentioning

confidence: 83%

“…5 The strain sensitivity obtained for the CO 2 -laser-induced LPFGs without physical deformation is usually very low, only −0.45 nm/ m . 2,3 In this letter, a technique of fabricating asymmetric LPFG by use of focused CO 2 laser beam to carve periodic grooves on one side of the optical fiber is presented. The LPFGs obtained exhibit a large peak transmission attenuation of −47.39 dB and a low insertion loss of 0.34 dB.…”

mentioning

confidence: 99%

“…By contrast, the peak attenuation of the LPFGs without periodic grooves is typically ϳ −25 dB. [1][2][3] Both the difference between the stretch-induced tensile strains in the grooved and the ungrooved regions and the amplitude of the stretch-induced microbends increase with the increase of the stretching force, which leads to the increase of ⌬n strain and ⌬n microbend . As shown in Fig.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Asymmetric long period fiber gratings fabricated by use of CO2 laser to carve periodic grooves on the optical fiber

Wang

Jin

et al. 2006

Applied Physics Letters

104

View full text Add to dashboard Cite

An asymmetric long period fiber grating ͑LPFG͒ with a large attenuation of −47.39 dB and a low insertion loss of 0.34 dB is fabricated by use of focused CO 2 laser beam to carve periodic grooves on one side of the optical fiber. Such periodic grooves and the stretch-induced periodic microbends can effectively enhance the refractive index modulation and increase the average strain sensitivity of the resonant wavelength of the LPFG to −102.89 nm/ m . The resonant wavelength and the peak attenuation of the LPFG can be tuned by ϳ12 nm and ϳ20 dB, respectively, by the application of a stretching force. © 2006 American Institute of Physics. ͓DOI: 10.1063/1.2360253͔ Long period fiber grating ͑LPFG͒ is one of the widely used passive optical fiber devices. Various LPFG fabrication techniques have been demonstrated, including ultraviolet laser irradiation, 1 CO 2 laser heat, 2,3 hydrofluoric acid etching corrugation, 4 and application of periodic microbend. 5 The strain sensitivity obtained for the CO 2 -laser-induced LPFGs without physical deformation is usually very low, only −0.45 nm/ m . 2,3 In this letter, a technique of fabricating asymmetric LPFG by use of focused CO 2 laser beam to carve periodic grooves on one side of the optical fiber is presented. The LPFGs obtained exhibit a large peak transmission attenuation of −47.39 dB and a low insertion loss of 0.34 dB. Moreover, the average strain sensitivity of resonant wavelength of the LPFG is increased to −102.89 nm/ m .Our experimental setup is shown in Fig. 1. A CO 2 laser ͑SYNRAD 48-1͒ with a maximum output power of 10 W, a light-emitting diode light source, and an optical spectrum analyzer ͑HP 70004A͒ were used. The optical fiber ͑Corning SMF-28͒ was situated in the focal plane of the CO 2 laser beam. One of the fiber ends was fixed and a small weight of ϳ5 g was used at the free end of the fiber to avoid the weight-induced macrobend and to provide a tensile strain in the fiber. The focused CO 2 laser beam scanned repeatedly for M times along the X direction at a location, corresponding to the first grating period, of the fiber via a two-dimensional optical scanner under the computer control. Then the laser beam was shifted by a grating period along the Y direction and scanned repeatedly for M times to generate the next grating period. This scanning and shifting process was carried out for N times ͑N is the number of grating periods͒ until the final grating period was created. The above mentioned process was repeated for K cycles until a high quality LPFG was produced. The repeated scanning of the focused CO 2 laser beam created a local high temperature in the fiber, which led to the gasification of SiO 2 on the surface of the fiber. As a result, periodic grooves were carved on the fiber as shown in Fig. 2. Such grooves induce periodic refractive index modulation along the fiber axis due to the photoelastic effect, thus creating a LPFG. The typical depth and width of the grooves obtained in our LPFGs were ϳ15 and ϳ50 m, respectively. The depth of the grooves dep...

show abstract

mentioning

confidence: 83%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Asymmetric long period fiber gratings fabricated by use of CO2 laser to carve periodic grooves on the optical fiber

Wang

Jin

et al. 2006

Applied Physics Letters

104

View full text Add to dashboard Cite

show abstract

“…As is well known, the use of hydrogen loading can enhance the photosensitivity of the Ge-doped fibers to ultra violet (UV) exposure [11]. Hydrogen loading is also found to enhance the writing efficiency of the CO 2 -laser-induced LPFGs [1,7]. Additionally, numerous experiments reveal that the writing efficiency of the CO 2 -laser-induced LPFGs could be enhanced by means of applying a tensile strain to the fiber employed during CO 2 laser irradiation [2,8,9], which may be due to the frozen-in viscoelasticity in the fiber.…”

Section: Introductionmentioning

confidence: 96%

“…Since Davis et al reported the first CO 2 -laserinduced long period fiber grating (LPFG) in a conventional glass fiber in 1998 [1], various CO 2 laser irradiation techniques have been demonstrated and improved to write high-quality LPFGs in different types of optical fibers such as conventional glass fibers [2,3], solid-core photonic crystal fibers [4,5], and air-core photonic bandgap fibers [6]. The enhancement of the grating-writing efficiency is critical to achieving a high-quality LPFG with desired mode-coupling efficiency.…”

Section: Introductionmentioning

confidence: 99%

Post-treatment techniques for enhancing mode-coupling in long period fiber gratings induced by CO2 laser

Tang

Zhao

et al. 2015

Photonic Sens

View full text Add to dashboard Cite

Two promising post-treatment techniques, i.e. applying tensile strain and rising temperature, are demonstrated to enhance the mode-coupling efficiency of the CO 2 -laser-induced long period fiber gratings (LPFGs) with periodic grooves. Such two post-treatment techniques can be used to enhance the resonant attenuation of the grating to achieve a LPFG-based filter with an extremely large attenuation and to tailor the transmission spectrum of the CO 2 -laser-induced LPFG after grating fabrication.

show abstract