Antimonene-gold based twin-core SPR sensor with a side-polished semi-arc groove dual sensing channel: an investigation with 2D material

Abstract

We propose surface plasmon resonance (SPR) based single-side polished photonic crystal fiber (SSP-PCF) sensor for low as well as high refractive index (RI) sensing. To achieve this, an active metal gold (Au) is deposited on the PCF's flat narrow channels to form a dual-sensing channel. Following that, a thin nanolayer antimonene is deposited on Au, as its buckled honeycomb lattice structure aids in the trapping of numerous biomolecules. For the sensing range of 1.27 to 1.39, numerical results show that the wavelength sensitivity (WS) and amplitude sensitivity (AS) mounted on 77,000 nmRIU−1 and 1320.41 RIU−1, respectively, with wavelength resolution (RW), and amplitude resolution (RA), as high as 1.298 × 10–6 RIU, and 8.6 × 10–7 RIU. The promising results obtained from the proposed SSP-PCF sensor offers improved refractive index sensing with a fine figure of merit (FOM), i.e., 311.74 RIU−1 for the sensing range of 1.27 to 1.39, which covers most known analytes such as proteins, cancer cells, glucose, viruses, DNA/RNA, medicinal drugs, halogenated organic acids. Further, the proposed sensor's design requires a simple fabrication procedure.