Graphene-Based Plasmonic Photonic Crystal Waveguide Integrated Biosensor Circuit

摘要

In this paper, we investigated the absorption and sensitivity of small refractive index (RI) changes due to high glucose concentration levels in a sample of urine using a graphene-based plasmonic photonic crystal waveguide (PCW) built into an integrated biosensor circuit (IBC). The design and characterization of the PCW structure were implemented using Finite Difference Time Domain (FDTD) and Waveguide Design Environment (MODE) whereas the IBC was designed using the INTERCONNECT module from Lumerical. The effective index and group index of the PCW were 1.4777 and 1.672 respectively. The fundamental mode was transverse electric (TE) at a wavelength of 0.8 mu m using surface plasmon resonance (SPR) sensing technique. The detection sensitivity is for RI ranging from 1.335 to 1.341. The detection of high glycosuria was obtained by transmission and reflection TE modes which refers to the input and output power levels at a frequency range of -0.2 THz to 0.2 THz. The input and output transmission power levels were 0.202845 mW to 0.202696 mW corresponding to -6.931548 dB to -6.928357 dB respectively. Reflection input and output range of power level were 0.0083993 mW to 0.0083825 mW corresponding to -20.757569 dB to -20.766264 dB respectively. Our designed IBC achieved detection sensitivity level of 7.48 mu m/RIU, deeming it to be suitable for biomedical applications.