Design and fabrication of one-dimensional photonic crystal as real time optical sensor for sugar solution concentration detection:
Abstract
This study is developed from the results of theoretical study of onedimensional photonic crystals with two defects that have unique characteristics in response of Photonic Band Pass (PPB) on the frequency interval of Photonic Band Gap (PBG). This study focused on prototyping photonic crystal sensor based on refractive index changes in a second defect that serves as a receptor in which to respond transmitansi value changes, so that could be used as a single-frequency index sensing. The reference wavelength that used in this study is 525 nm. This research was conducted with some of the following stages: theoretical model of observation through implementation and simulation, fabrication of photonic crystal, characterization, sensing test, assembly and instrumentation devices, and device performance measurement. Fabrication process of a prototype of this system by means of electron beam evaporation equipment in a sample chamber at pressure of 10-3 Pa with BK-7 glass substrate at temperature 573 K. Each of the photonic cells is composed of a high index layer of OS-5 with refractive index of n 2.10 , and an equal optical thickness low index layer of MgF2 with n 1.38. In the first defect cell, the high index layer has twice the thickness of the other layers with the low index layer left unchanged, while in the second defect cell separated by 6 unit cells, the first layer is void to be filled with the sample solution.