This article presents a novel photonic crystal fiber-based surface plasmon resonance (PCF-SPR) sensor designed for cancer cell detection within the human body. The sensor’s construction involves precise chemical vapor deposition (CVD) to deposit gold, a plasmonic material, on both parallel and opposing peripheral sections of the PCF lattice. The dual-side polished PCF-SPR sensor is systematically positioned near a solution containing cancer cells awaiting detection. An external sensing system monitors changes in the SPR phenomenon, enabling the precise measurement of the refractive index (RI) of the scrutinized cancer cells. The PCF-SPR sensor’s intricate design and numerical exploration of its structural parameters are methodically conducted using COMSOL Multiphysics software, employing a full vectorial finite element method (FEM) to ensure accuracy and reliability in performance evaluation. Simulation results reveal critical parameters: a maximum wavelength sensitivity of 7143 nm/RIU, amplitude sensitivity of -270 RIU ^-1 , sensor resolution of 2.9×10 ^-5 RIU, and a figure of merit (FOM) of 900. With its streamlined structure, minimal air hole count, and exceptional sensitivity, the proposed PCF-SPR sensor holds significant promise for accurate cancer cell detection within the human body. This innovation has the potential to greatly enhance healthcare diagnostics, offering a more effective and precise means of identifying cancerous cells to improve patient care.

An optical fiber having the properties of photonic crystal and offering new diversity and features beyond a conventional optical fiber is the photonic crystal fiber (PCF). In this paper, a simplified version of a highly sensitive plasmonic sensor, called a “slotted PCF based plasmonic biosensor,” is studied numerically with asymmetric air holes using the finite element method. From numerical records through the interrogation method, the maximum obtained wavelength sensitivity and amplitude sensitivity are 22000 nm/RIU and 1782.56 R I U − 1 , respectively, with a maximum wavelength resolution of 4.54 × 10 − 6 R I U − 1 RIU for the y -polarized mode. Finally, optimization of the sensor performance is scrutinized, and the effect of different parameters is studied with proper resonance wavelength curve fitting. The design structure of the fiber is simple, symmetrical, easy to fabricate, and cost effective and has higher sensitivity than other PCF based sensors. Having a symmetric orientation of air holes, classic geometric structure, and higher sensitivity, it has the capability to be used in sensing applications, refractive index detection, and identification of biochemicals, biomolecules, and other analytes.

We report on a polymer-based porous-core photonic crystal fiber for simultaneous high-birefringent and low-loss propagation of narrowband terahertz (THz) electromagnetic waves. The high birefringence is induced by using rotated elliptical air holes inside the porous-core. The fiber is numerically analyzed with an efficient finite-element method. The simulation results exhibit an extremely high birefringence of $∼0.042$ and a very low effective material loss of $∼0.07cm−1$ at an operating frequency of 1 THz. Moreover, we have found an optimal $rotation angle(θ)=n30deg$ ($n$ is an odd integer). Other modal features of the fiber, such as confinement loss, power fraction, effective area, bending loss, and dispersion, also have been analyzed. We anticipate that the proposed fiber would be suitable in polarization maintaining THz wave guidance applications.

A porous-core octagonal photonic crystal fiber (PC-OPCF) with ultralow effective material loss (EML), high core power fraction, and ultra flattened dispersion is proposed for terahertz (THz) wave propagation. At an operating frequency of 1 THz and core diameter of $345μm$, simulation results display an extremely low EML of $0.047cm−1$, 49.1% power transmission through core air holes, decreased confinement loss with the increase of frequency, and dispersion variation of $0.15ps/THz/cm$. In addition, the proposed PCF can successfully operate in single-mode condition. All the simulations are performed with finite-element modeling package, COMSOL v4.2. The design can be fabricated using a stacking and drilling method. Thus, the proposed fiber has the potential of being an effective transmission medium of broadband THz waves.

A triangular lattice dispersion compensating photonic crystal fiber is presented in this paper. The fiber produces high birefringence and operates at fundamental mode only. The full vector finite element method with a perfectly matched absorbing layer boundary condition is applied to investigate the guiding properties of the proposed fiber. The designed fiber demonstrates that it is possible to obtain a very large negative dispersion of $-9486.1\mathrm{ps}/(\mathrm{nm}·\mathrm{km})$ at 1550 nm wavelength with a negative dispersion more than $-7000\mathrm{ps}/(\mathrm{nm}·\mathrm{km})$ over the entire C-band (1530–1565 nm), which is suitable for broadband dispersion compensation. The birefringence is about $4.13\times {10}^{-2}$ at 1550 nm wavelength, which is also very high. All these properties make this fiber very suitable in the area of broadband dispersion compensation and polarization-maintaining applications.

We propose the design of a novel porous-core honeycomb lattice photonic crystal fiber (PH-PCF) with extremely low loss and flattened dispersion for guiding terahertz (THz) wave. Finite element method (FEM) is used to investigate in detail the properties of the designed waveguide. The single modeness, effective material loss (EML), confinement loss (Lc), effective modal area, bending loss, distribution of power in different regions, and the dispersion profile of the designed structure are systematically analyzed. Simulation results of the proposed PHPCF confirm that the bulk material absorption loss of the host material Topas can be reduced by 88.87% using the proposed design. The obtained EML is as low as 0.02227 cm-1 at operating frequency f = 1 THz and the dispersion is ±0.15 ps/THz/cm, flattened over a band of frequency as wide as 1.15 THz. Besides, the reported design also offers negligible Lc and relatively smaller bending loss as compared to other contemporary studies.