Sensitivity enhancement of SPR biosensor employing heterostructure blue phosphorus/MoS2 and silicon layer

Abstract

Present study proposed three new Kretschmann configuration based heterostructure surface plasmon resonance sensor for biomolecule detection. The thickness of silver, silicon and heterostructures BlueP/MoS2 layers are optimized under the consideration of less reflectivity, full width at half maxima and enhanced sensitivity. After thickness optimization, the performance parameters of the proposed SPR sensor have also been calculated in terms of sensitivity, quality factor, and detection accuracy. The performance effected by increasing the number of heterostructure BlueP/MoS2 layer is also analyzed. It is also observed that Si layer plays an important role to enhance all performance parameters when it is deposited between silver and heterostructure BlueP/MoS2 layer. The optimized sensitivity at wavelength 633 nm of the heterostructure BlueP/MoS2 monolayer and silicon layer is 282°RIU−1. The highest optimized sensitivity 328°RIU>−1 is achieved with two layers of heterostructure BlueP/MoS2 having thickness of silicon layer 5 nm. It is found that sensitivity is increased by 16% when number of heterostructure layers has changed. Another important parameter like detection accuracy, quality factor, Full width at half maximum have been also calculated for proposed SPR sensor. The TM (transverse magnetic) field plot and PD (penetration depth) 138.25 nm of the proposed SPR sensor have been also calculated.