Design and Crystal Engineering of a Photonic Crystal Fiber for Optical Pressure Sensing

Photonic crystal fibers (PCFs) have attracted considerable interest due to their unique microstructured geometry and their ability to manipulate optical properties through structural design. In this work, a novel photonic crystal fiber configuration is proposed and investigated for pressure sensing applications. The structure is based on a silica background with a periodic arrangement of air holes forming a photonic crystal cladding. By engineering the geometrical parameters of the microstructured lattice and selectively infiltrating water into the air holes, the optical behavior of the fiber can be significantly modified.

Numerical simulations were carried out to analyze the influence of pressure variations on the chromatic dispersion characteristics of the proposed structure. The study demonstrates that the infiltration of water into the microstructured regions strongly affects the dispersion profile and shifts the zero-dispersion wavelength of the fiber. This behavior highlights the strong interaction between the guided optical field and the infiltrated medium, which can be exploited for sensing purposes.

Furthermore, the pressure sensitivity of the proposed sensor was evaluated by analyzing the variation in chromatic dispersion at different operating wavelengths. The results indicate that the sensor exhibits enhanced sensitivity at longer wavelengths, demonstrating the potential of the proposed design for high-precision pressure detection.

Compared with previously reported photonic crystal fiber sensors, the engineered structure shows improved sensing performance due to the optimized microstructured design and the interaction between the optical field and the infiltrated liquid. These findings demonstrate that crystal-engineered photonic crystal fibers can provide an effective platform for the development of highly sensitive optical pressure sensors for various scientific and industrial applications.