The Related Research About The New Performance Of The Surface-relief Microfiber Bragg Gratings And The New Phase Shift Grating

As a key optical components, fiber gratings become one of the most development prospects and the most representative optical fiber passive components. At the same time, Fiber Bragg grating has been widely used in optical fiber communication, optical fiber sensing and optical information processing and other fields. The study of the different structure,property and potential using field of the fiber grating make the preparation method and using features of the new fiber Bragg grating win the favour of the researchers.The first part of this article is based on the new composite nanoimprint lithography technology which is our group’s development. We theoretical simulate and research in the preparation technology the parameters such as the different etching depth and fiber diameter impact on the reflection properties of the surface-relief microfiber Bragg gratings. Through using the coupled-mode theory simulating the surface-relief microfiber Bragg gratings, we studied the bandwidth of reflection spectrum trend to change with the change of the etching depth, the resonance wavelength of reflection spectrum trend to change with the change of the period and the external refractive index, the resonance wavelength and the bandwidth trend to change with the change of the fiber diameter and the reflectivity of reflection spectrum trend to change with the change of the length. We measure the change of the location of the resonance wavelength, actually measuring the changes of period or external refractive index, finally obtained the corresponding changes in the external stress or external material. We utilizing the changes of the etching depth and the fiber diameter make the bandwidth of reflection spectrum narrower, improve the wavelength selectivity, and apply it to the laser and DWDM.In the second part of this paper we study the surface-relief phase-shifted gratings and the superiority compared with the traditional phase-shifted grating.And we study the phenomenon of the same peaks caused by the change of the position of phase shift. As the etching depth is 400 nm, the FWHM of the reflection spectrum of the surface-relief phase-shifted gratings is 7 nm, and the FWHM of the reflection spectrum of the transmission window is 0.1 nm. So we can improve the wavelength selectivity, which is applied to narrow-band laser. As the following, we simulate the graph of reflection spectrum with six phase shifts and ten phase shifts which have the same peaks.Due to the surface-relief microfiber Bragg gratings has small size, high temperature resistant, compatible with fiber, good mechanical strength, scattered wave which can be measured and has a higher sensitivity to the environment, which may be used in micro-nano photonic devices in the micro small filter, fiber resonator and laser, and become a new kind of micro-nano photon function structure uniting optical fiber and nanotechnology.