Tiesheng Wu

The sensing characteristics of plasmonic waveguide with a ring resonator

A surface plasmon polaritons (SPPs) refractive index sensor which consists of two metal-insulator-metal (MIM) waveguides coupled to each other by a ring resonator is proposed. The transmission properties are numerically simulated by finite element method. The sensing characteristics of such structure are systematically analyzed by investigating the transmission spectrum. The results indicate that there exist three resonance peaks in the transmission spectrum, and all of which have a linear relationship with the refractive index of the material under sensing. Through the optimization of structural parameters, we achieve a theoretical value of the refractive index sensitivity as high as 3460nmRIU(-1). Furthermore, this structure can also be used as a temperature sensor with temperature sensitivity of 1.36nm/°C. This work paves the way toward sensitive nanometer scale refractive index sensor and temperature sensor for design and application.

Tuning the Fano resonances in a single defect nanocavity coupled with a plasmonic waveguide for sensing applications

A novel surface plasmon polaritons (SPPs) refractive index sensor based on a single defect nanocavity coupled with a metal–insulator–metal (MIM) waveguide is proposed and numerically simulated by using the finite difference time domain (FDTD) method with perfectly matched layer absorbing boundary condition. It is found that the defect structure can realize two Fano resonances and these two Fano resonances originate from two different mechanisms. The results demonstrate the liner correlation between the resonance wavelengths of the device and the refractive index of the material under sensing. Through the optimization of structural parameters, we achieve a theoretical value of the refractive index sensitivity as high as 1800.4 nmRIU−1. It could be utilized to develop ultra-compact nanodevice for high-resolution biological sensing.

Temperature characteristics of high birefringence photonic crystal fiber filled with liquid

In this paper, the theoretical model of high birefringence photonic crystal fiber(PCF) has proposed by the plane wave expansion method. The temperature impacts of the birefringence and beat length in high birefringence PCF which filled with ethanol were numerical analyzed. The results show the refractive index of filling liquid significantly influence on the birefringence and beat length. When the wavelength increases, the birefringence increases while the beat length decreases, when the temperature increases, the birefringence also increases while the beat length decreases. In addition, the temperature affected the birefringence and beat length. Especially the birefringence of high birefringence PCF is more sensitive to temperature. When the wavelength is longer, these results for design temperature sensors have certain reference significance.

Analyses of birefringence photonic crystal fiber with liquid for temperature sensor

In this paper, the high thermo-optic coefficient, and enhancing sensitivity with temperature, high birefringence PCF filled in ethanol was manufactured by temperature sensor of filling the air holes with ethanol. The theoretical model of high birefringence PCF has proposed by the plane wave expansion method, at the same time the temperature impacts of the birefringence and beat length in high birefringence PCF which filled with ethanol were numerical analyzed. The birefringence increases as a beat length decreases with a wavelength increases. Especially high birefringence PCF is more sensitive to temperature with the long wavelength, which is a reference significance in useful to design temperature sensors.

A HBF strain sensor with piezoelectric ceramic based on Sagnac LM

In this paper, the characteristics of the high birefringence fiber (HBF) strain sensor based on piezoelectric ceramic have researched, and analyzed with the force of piezoelectric ceramic because the voltage applied on HBF and the force of the HBF wounded on the piezoelectric ceramic. We can get the relationship between the applied voltage and the shift of the trough wavelength by calculating the equation of the shift of birefringence and trough wavelength, at the same time, compared the experimental with fitting curves and the difference between elliptical fiber and panda fiber. Then connect the fiber sensing experiment based on the piezoelectric ceramic with the fiber temperature sensing experiment, and change the temperature and the stress individually. Lastly analyze the results of the joint experiments.

Temperature sensor characteristics of photonic crystal fiber in filling methanol

In this paper, the affection of the effective index and normalized frequency with the temperature have researched based on filling methanol in photonics crystal fiber with the hexagon structure. The theoretical model of the total internal reflection photonics crystal fiber has studied on plane-wave expansion technique. The results of the total internal reflection photonic crystal fiber (TIR-PCF) temperature characteristics have obtained in filling the high refractive index temperature coefficient liquid material. The refractive index of filling liquid and temperature affect on the effective refractive index and normalized frequency. The effective refractive index will reduce and normalized frequency will increase as the temperature increases. When the distance between adjacent holes Λ remains unchanged, the ratio of diameter of holes d and Λ of d/Λ is greater and the input wavelength is longer, the effective refractive index with the temperature becomes the most sensitively. The properties are valuable for design and application of temperature sensors.