Single and bimetal-based surface plasmon resonance sensor using AlN-TMDC heterostructure: a comparison study

摘要

In this work, the performance of a single/ bimetal based surface plasmon resonance (SPR) sensor is probed utilizing a two-dimensional heterostructure composed of aluminium nitride (AlN) and transition-metal dichalcogenide (TMDC). The heterostructure is placed on the optimized Silver-Gold bimetal surface instead of single metal to achieve a stable sensor surface and better response. The presence of a high index AlN layer helps to enhance the sensitivity and TMDC material aids to adsorb more target biological molecules, with protection underneath layers from oxidation. To get a better response different heterostructures (AlN-TMDC) are incorporated into the structure and found that AlN-tungsten disulfide (WS2) outperforms others. The observed values of sensitivity, detection accuracy (DA), and figure of merits (FOM) are 179.00063 (degrees/RIU), 0.7294, and 46.1342 (RIU-1) respectively. Also, the evanescent electric field at the sensor interface provides maximum intensity (1.68E-04 V/nm) which is confirmed by the finite element analysis (FEA). The authors believe that the outcomes of this work will be beneficial to develop a highly sensitive and stable plasmonic device for different healthcare applications.