Nowadays, plasmonic sensors based on photonic crystal fiber (PCF) attracted a great deal of attention in the field of optical sensing. Opening-up dual-core photonic crystal fibers based on surface plasmon resonance (SPR) are numerically demonstrated and analyzed for detecting a wide refractive index (RI) range by the finite-difference time-domain method (FDTD). Wavelength and amplitude integration methods as well as figures of merit are used to investigate the sensing performance. For improving sensing performance, a large hole between two cores in the opening-up section is introduced. The opening-up section as a sensing channel is coated with a gold film and a thin titanium dioxide (\({TiO}_{2}\)) layer. By surface engineering including imposing of grating on the gold film, specification of optimized values of different layers located near the surface and sensing performance are investigated. Next, the effect of the fiber structural parameters is analyzed to enhance SPR and fundamental core mode coupling. The proposed sensor revealed maximum wavelength and amplitude sensitivities of 15,167 \(\left(\frac{nm}{RIU}\right)\) and 207.19 \(\left({RIU}^{-1}\right)\), respectively. Due to the ease of infiltration of analyte and gold coating and thanks to the high wavelength and amplitude sensitivity, the sensors can be a promising candidate for physical and chemical sensing.

如今，基于光子晶体光纤（PCF）的等离子体传感器在光学传感领域引起了极大的关注。对基于表面等离子体共振 (SPR) 的开放式双芯光子晶体光纤进行了数值演示和分析，以通过有限差分时域方法 (FDTD) 检测宽折射率 (RI) 范围。波长和幅度积分方法以及品质因数用于研究传感性能。为了提高传感性能，在开放部分的两个磁芯之间引入了一个大孔。作为传感通道的开放部分涂有金膜和薄二氧化钛（\({TiO}_{2}\)） 层。通过表面工程，包括在金膜上施加光栅，研究了位于表面附近的不同层的优化值的规格和传感性能。接下来，分析了光纤结构参数对增强 SPR 和基芯模式耦合的影响。所提出的传感器显示最大波长和幅度灵敏度为 15,167 \(\left(\frac{nm}{RIU}\right)\)和 207.19 \(\left({RIU}^{-1}\right)\)，分别。由于分析物和金涂层易于渗透，并且由于具有高波长和幅度灵敏度，因此传感器可以成为物理和化学传感的有希望的候选者。