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提出了一种具有增强灵敏度的锥形光纤二硫化钨(WS2)-金(Au)表面等离子体共振(SPR)传感器.通过传输矩阵方法对传感器进行了理论模拟,评估了传感器的可行性.在锥形光纤上依次涂覆WS2和溅射金膜进行传感实验,该传感器的实验折射率灵敏度可达4158.171 nm/RIU,比多模光纤SPR传感器提高了125.8％,比锥形光纤Au-WS2 SPR传感器提高了50.1％.此外,该传感器中的WS2不易脱落,表现出良好的可靠性.该传感器结构简单、易于制造,具有高的折射率灵敏度,在生化传感领域具有良好的应用前景.“,”Fiber optic SPR sensors have wide application prospects in the field of biosensing due to the advantages of label-free,fast response in real-time,and good biocompatibility. Traditional multimode fiber optic SPR sensors are limited by low sensitivity,which leads to their insufficient performance in the detection of low-concentration analytes. Therefore,improving the sensitivity of fiber optic SPR sensors and applying them to trace detection of biomolecules have received increasing attention from researchers. There are two main ways to improve sensitivity. One is to increase the strength of the evanescent field by changing the structure of fiber (e. g. U-shaped,D-shaped,tapered,etc.),and the other is to use the excellent photoelectric properties of new materials(e. g. high refractive index oxides,ceramic materials, two-dimensional materials,etc.)to improve the sensitivity of the sensor. Similar to graphene,Transition Metal Dichalcogenides(TMDCs)have also attracted much attention. Among them,Tungsten disulfide (WS2)shows many unique optoelectronic properties such as high complex RI ratio(the ratio of the real part to the imaginary part of the RI),direct band gap and large surface-to-volume ratio. It is shown that the application potential of WS2 in SPR sensors. However,there are relatively few experimental studies of WS2 in SPR sensors,and they mainly focus on prism-based SPR sensors.Based on the above-mentioned methods,the sensitivity of the fiber optic SPR sensor is improved by combining the tapering of the fiber and the coating of WS2 nanomaterials. In this paper,a tapered fiber optic SPR sensor based on the structure of WS2-Au is proposed. The relationship between the dielectric constant of WS2 and the wavelength is obtained by the first principles using the generalized-gradient approximation. The effects of taper ratio and the thickness of WS2 on the sensitivity of sensors are studied through theoretical simulations used the transfer matrix method. Then,four kinds of sensors(600μm fiber SPR sensor,tapered fiber SPR sensor, tapered fiber Au-WS2 SPR sensor and tapered fiber WS2-Au SPR sensor) are manufactured. Among them,the WS2 nanosheets are modified on the fiber surface using electrostatic self-assembly technology, and the Au film is obtained by vacuum magnetron sputtering coating technology. An experimental setup is built to measure their Refractive Index(RI)sensitivity. The experimental RI sensitivity of the proposed tapered fiber WS2-Au SPR sensor can reach 4158.171 nm/RIU,which is 125.8％ higher than that of the multimode fiber SPR sensor and 50.1％ higher than that of the tapered fiber Au-WS2 SPR sensor. Experimental results show a good agreement with the numerical simulations. It is demonstrated that the introduction of the WS2 layer can improve the sensitivity of the fiber optic SPR sensor and enhance the reliability of the sensor. In summary,the developed sensor can provide a high-sensitivity,low-cost, simple and environment-friendly platform for the biochemical detection.