Dynamically modulated intensity interrogation scheme using waveguide coupled surface plasmon resonance sensors

作者：Ma, Xin; Xu, Xinlong; Zheng, Zheng; Wang, Kun; Su, Yalin; Fan, Jiangfeng; Zhang, Rui; Song, Lusheng; Wang, Zhiyou; Zhu, Jinsong^*

来源：Sensors and Actuators A: Physical , 2010, 157(1): 9-14.

DOI：10.1016/j.sna.2009.11.004

• Optical sensing and sensors
• Surface plasmon
• Modulation
• Polymer active device

An electro-optically modulated intensity interrogation method based on tunable waveguide coupled surface plasmon resonance sensors has been proposed. It has been theoretically and experimentally demonstrated that the proposed scheme can enable sensitive measurement of measure and variations. By modulating the refractive index in the waveguide layer, this interrogation method yields modulated signal whose amplitude is related to measurand's refractive index. This amplitude modulated signal offers a higher signal to noise ratio and eliminates additive noise in the sensor system. A preliminary investigation using saline buffers with different NaCl concentrations shows a resolution of 2.3 x 10(-6) refractive index unit by our approach. Resolution can be controlled by the amplitude of the applied modulation voltage and can be further enhanced by optimizing the device structure or improving the electro-optical (E-O) coefficient of the E-O material. This approach is simple, stable, and promising for low-cost or multi-channel SPR biosensor applications.

• 出版日期2010-1
• 单位北京航空航天大学; 国家纳米科学中心