Type IIa Bragg gratings formed in microfibers.

In this Letter, Type IIa Bragg gratings are inscribed into microfibers. The large germanium-doped core region of the multimode fiber provides the necessary photosensitivity to form a Type IIa grating when it is drawn down to the microscale. Reducing the diameter of the microfiber due to lower saturate modulation and the amplified tension-strain transformation effect can accelerate the formation of a Type IIa grating. This provides an efficient method for the fabrication of fiber gratings with 800°C temperature resistance.

[1]  Om Prakash,et al.  Enhanced Temperature $({\sim}{800}^{\circ}{\rm C})$ Stability of Type-IIa FBG Written by 255 nm Beam , 2014, IEEE Photonics Technology Letters.

[2]  C. Liao,et al.  Femtosecond laser fabricated fiber Bragg grating in microfiber for refractive index sensing. , 2010, Optics letters.

[3]  Stephen F Collins,et al.  Reflections near 1030 nm from 1540 nm fibre Bragg gratings: Evidence of a complex refractive index structure , 2005 .

[4]  I. Riant,et al.  Study of the photosensitivity at 193 nm and comparison with photosensitivity at 240 nm influence of fiber tension: type IIa aging , 1997 .

[5]  L Reekie,et al.  Negative-index gratings formed by a 193-nm excimer laser. , 1996, Optics letters.

[6]  Bai-Ou Guan,et al.  High-efficiency ultraviolet inscription of Bragg gratings in microfibers , 2012, IEEE Photonics Journal.

[7]  Ming Ding,et al.  A compact broadband microfiber Bragg grating. , 2011, Optics express.

[8]  Ian Bennion,et al.  Dependence of temperature and strain coefficients on fiber grating type and its application to simultaneous temperature and strain measurement. , 2002, Optics letters.

[9]  H. Limberger,et al.  UV-irradiation-induced structural transformation of germanoscilicate glass fiber. , 1997, Optics letters.

[10]  M. Konstantaki,et al.  Accelerated recording of negative index gratings in Ge-doped optical fibers using 248-nm 500-fs laser radiation , 2006, IEEE Photonics Technology Letters.

[11]  Limin Tong,et al.  Compact microfiber Bragg gratings with high-index contrast. , 2011, Optics letters.

[12]  Liang Dong,et al.  Evidence by transmission electron microscopy of densification associated to Bragg grating photoimprinting in germanosilicate optical fibers , 1997 .

[13]  Yu Zhang,et al.  Refractive index sensing based on higher-order mode reflection of a microfiber Bragg grating. , 2010, Optics express.

[14]  Liang Dong,et al.  UV-irradiation induced stress and index changes during the growth of type-I and type-IIA fiber gratings , 2003 .

[15]  Bai-Ou Guan,et al.  193 nm excimer laser inscribed Bragg gratings in microfibers for refractive index sensing. , 2011, Optics express.

[16]  G. Baxter,et al.  Numerical investigation on the effects of fabrication conditions on fiber Bragg grating spectra using the phase mask technique. , 2013, Applied optics.

[17]  S. Wade,et al.  Variations of the growth of harmonic reflections in fiber Bragg gratings fabricated using phase masks. , 2012, Journal of the Optical Society of America. A, Optics, image science, and vision.

[18]  Yan-qing Lu,et al.  Ultra-highly sensitive surface-corrugated microfiber Bragg grating force sensor , 2012 .

[19]  J. Canning.  Fibre gratings and devices for sensors and lasers , 2008 .

[20]  John Canning,et al.  Enhanced type IIA gratings for high-temperature operation. , 2004, Optics letters.

[21]  Type IIA Grating Inscription in a Highly Nonlinear Microstructured Optical Fiber , 2009, IEEE Photonics Technology Letters.