Evanescent Field-based Sensor Design Using Uniform Strips on SOI-based Slot Type of Waveguide for Brain Cancer Application

Introduction: The slot type of photonic waveguide is commonly used in designing sensors based on the evanescent field because of its high evanescent field characteristics. Methods: In this study, we introduced multiple uniform strips to improve the performance of the waveguide, aiming for a higher evanescent field ratio and reduced propagation loss to optimize the effectiveness of the sensor. The inclusion of uniform strips enhances the overall capabilities of the waveguide for evanescent field-based sensing applications. Results: The investigation showed that the one-strip and three-strip design structures achieved maximum evanescent field values of 0.43 and 0.38, respectively, indicating significant levels. However, the three-strip design structure exhibited the minimum propagation loss, recorded at 9.1 dB/cm. Considering the variations in Evanescent Field Ratio (EFR) and propagation loss, the slot waveguide with three strips emerges as a potentially optimal design structure. Conclusion: This conclusion is particularly relevant in the context of brain cancer applications, where heightened sensitivity is crucial. Therefore, the three-strip configuration shows promise for superior performance in detecting and addressing the complexities of brain cancer.