基于可调谐光子晶体谐振腔的生物传感器研究

In this paper, the 3D FDTD algorithm is used to design the photonic crystal cavity. Through the research of the transmission spectrum of the photonic crystal cavity, we find the transmission peak is located at the wavelength of 1397nm and the peak value is 0.822. Quality factor is a very important parameter of the photonic crystal cavity. So we study the tunable property of the photonic crystal structure and obtain the best Q value of the photonic crystal cavity with the method of changing the structure of it. The specific method is to change the radius of the central air hole in the cavity. The results show that the quality factor Q reached the maximum value at r=0.06μm with the vaule is 288.96. The model of photonic crystal cavity with different refractive index on the biological samples' surface is simulated. Our study shows that the center wavelength of the transmission peak of the photonic crystal cavity is sensitive to the change of refractive index of the biological samples. The function of the biological sensing can be realized and the sensitivity is 7.5nm/RIU.