This work presents a highly sensitive plasmonic refractive index (RI) sensor on a dual core photonic crystal fiber (PCF). The performance of the RI sensor is weighed in terms of amplitude sensitivity, wavelength sensitivity, wavelength resolution, and linearity of the resonance wavelength. Numerical result shows that the maximum amplitude sensitivity of 725.8918 RIU-1 and 1085 RIU-1 are achieved for x-and y-polarization, respectively, by using amplitude interrogation method. In addition, wavelength interrogation method gives the maximum wavelength sensitivity of around 9000 nm/RIU for both x-and y-polarized modes. Moreover, the maximum wavelength resolution of 1.11×10-5 RIU and the value of the co-efficient of determination (R2) of 0.9784 are reported. The proposed high performance plasmonic RI sensor can be a favorable candidate for the detection of biological and biochemical analytes.

In this article, an antiresonant nodeless hollow core fiber having nested hybrid cladding elements is proposed without having large distance between core and jacket capillary. The presented anisotropic construction (elliptical nesting in circular tube) with optimized curvature factor, strut thickness, and gap between adjacent tubes lead to extremely low loss over wide band compared to existing structures (circular, circular nested, elliptical, elliptical nested). The results show the lowest confinement loss of 0.0007 dB/km at 1.06 m with maintaining a loss of less than 0.003 dB/km over 670 nm (0.90 m to 1.57 m) bandwidth. In addition, the lowest surface scattering loss of 0.01 dB/km is achieved along with better bending stability and effective single mode operation. The proposed fiber may have potential opportunity in optical communication systems for its low-loss transmission over wideband region.

A numerical analysis on dual core photonic crystal fiber (DC-PCF) based surface plasmon resonance (SPR) refractive index sensor is presented. The guiding parameters and required sensing performances are examined with finite element method (FEM) based software under MATLAB environment. According to simulation, it is warrant that the proposed refractive index sensor offers the maximum amplitude sensitivity of 554.9 refractive index unit (RIU⁻¹) and 636.5 RIU⁻¹ with the maximum wavelength sensitivity of 5800 nm/RIU and 11 500 nm/RIU, and the sensor resolution of 1.72 × 10⁻⁵ RIU and 8.7 × 10⁻⁶ RIU, at analyte refractive index (RI) of 1.40 for x- and y-polarized modes, respectively. As the sensing performance in different wavelength ranges is quite high, the proposed sensor can be used in simultaneous detection for different wavelength ranges. Therefore, the proposed device is of a suitable platform for detecting biological, chemical, biochemical, and organic chemical analytes.

A compact polarization beam splitter based on a gold-filled photonic crystal fiber with a square lattice is proposed. The full vector finite element method is used to design and characterize the proposed ultra-compact and ultra-broadband polarization splitter. The plasmonic plays an important role in order to achieve an ultra-short length of 56.33 µm with a high extinction ratio of 132.92 dB at the wavelength of 1.55 µm. It can ensure an ultra-broad bandwidth of 530 nm, from 1225 to 1755 nm, covering all the communication bands with an extinction ratio better than 20 dB. The proposed polarization splitter may be a promising candidate in communication due to its ultra-short length and ultra-broad bandwidth.

A polarization splitter based on gold filled dual-core photonic crystal fiber (DC-PCF) that can work from 1420 nm to 1980 nm (560 nm bandwidth) is proposed in this work. The splitter has an extinction ratio lower than −20 dB over a large bandwidth with a total length of 254.6 μm. The key principle of operation of the splitter is the induced change in the refractive index of the y-odd mode when it is coupled to the second order plasmonic mode, while other supermodes are weakly affected by the plasmonic mode. The proposed broadband and compact polarization splitter may find applications in communications and sensing, being capable of working in the infrared and mid-infrared wavelength ranges.