Surface plasmon resonance sensor based on polarization interferometry and angle modulation.
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.
Sun
Zhanliang
Z
Laboratory of Optical Imaging and Sensing, Graduate School of Shenzhen, Tsinghua University, China.
He
Yonghong
Y
Guo
Jihua
J
D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007368:Interferometry / Q000295:instrumentation* / Q000379:methods; D008859:Microscopy, Polarization / Q000295:instrumentation* / Q000379:methods; D012031:Refractometry / Q000295:instrumentation* / Q000379:methods; D020349:Surface Plasmon Resonance / Q000295:instrumentation* / Q000379:methods; D014159:Transducers