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Surface plasmon resonance sensor based on polarization interferometry and angle modulation.

Zhanliang Sun·Yonghong He·Jihua Guo
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Abstract

A surface plasmon resonance (SPR) sensing technique based on polarization interferometry and angle modulation is presented. Its sensitivity is not a direct function of variation of reflection intensity, nor of phase shift. Rather, it is a function of the complex reflection coefficient. A three times standard deviation detection limit of 5.1 x 10(-7) refractive index units in a 2 Hz bandwidth is obtained with our experimental setup. A theoretical analysis shows that this technique can provide a wide linear measurement range. Moreover, the sensitivity is insensitive to the thickness of gold films over approximately 5 nm. This SPR sensing technique is suitable for physical, chemical, and biological research.

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Computer-Aided DesignEquipment DesignEquipment Failure AnalysisInterferometryMicroscopy, PolarizationRefractometrySurface Plasmon ResonanceTransducersJournal ArticleResearch Support, Non-U.S. Gov't

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Zhanliang Sun, Yonghong He, Jihua Guo. 2006-05-01. Surface plasmon resonance sensor based on polarization interferometry and angle modulation.. https://doi.org/10.1364/ao.45.003071

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