A Magnetic Field SPR Sensor Based on Temperature Self-Reference

In this paper, a novel D-shaped photonic crystal fiber sensor for simultaneous measurements of magnetic field and temperature is proposed and characterized. Based on the surface plasmon resonance theory, the D-shaped flat surface coated with a gold layer is in direct contact with magnetic fluid to detect magnetic field, and one of the relatively small air holes near the fiber core is filled with polydimethylsiloxane (PDMS) to sense temperature. The realization of measuring the magnetic field and temperature separately through two channels depends on the fact that the magnetic field only changes the refractive index of the magnetic fluid, but has no effect on the refractive index of PDMS. The refractive index of the magnetic fluid and PDMS can be affected by temperature at the same time. The sensor designed in this work can separate the variations of the magnetic field and temperature simultaneously, therefore solving the cross-sensitivity problem to further improve the magnetic field sensitivity. When the thickness of the gold film is 50 nm and the radius of the filling hole is 0.52 µm, the magnetic field sensitivity and the temperature sensitivity of magnetic field sensor based on temperature self-reference can reach 0.14274 nm/Oe and −0.229 nm/°C, respectively.

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A Highly Magnetic Field Sensitive Photonic Crystal Fiber Based on Surface Plasmon Resonance

Sensors ◽

10.3390/s20185193 ◽

2020 ◽

Vol 20 (18) ◽

pp. 5193 ◽

Cited By ~ 2

Author(s):

Huimin Huang ◽

Zhenrong Zhang ◽

Yang Yu ◽

Lingjun Zhou ◽

Yuyu Tao ◽

...

Keyword(s):

Magnetic Field ◽

Refractive Index ◽

Surface Plasmon Resonance ◽

Photonic Crystal ◽

Photonic Crystal Fiber ◽

Surface Plasmon ◽

Plasmon Resonance ◽

Crystal Fiber ◽

Field Sensor ◽

The Magnetic Field

A novel magnetic field sensor comprising a photonic crystal fiber (PCF) is designed and investigated based on surface plasmon resonance (SPR). We use finite element analysis in order to analyze the sensing characteristics of the magnetic field sensor. The simulation results show that the sensor is very sensitive to the change of refractive index and has good linearity in the refractive index range from 1.43–1.45. The thickness of the metal film and the metal material has great influence on the resonance wavelength and the peak of the loss spectrum, the diameter of the central air hole will affect SPP excitation. When the thickness of gold layer is 50 nm, the refractive index sensitivity is 4125 nm/RIU in the refractive index range from 1.43–1.45. Using the designed sensor for magnetic field sensing, the loss spectrum is red-shifted with the increase of the magnetic field, the highest magnetic field sensitivity can reach 61.25 pm/Oe in the range from 50 Oe to 130 Oe. The sensor not only has high sensitivity of refractive index, but it can also realize accurate measurement of magnetic field. It has huge application potential in complex environment, remote sensing, real-time monitoring, and other fields.

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Magnetic-field sensor with self-reference characteristic based on a magnetic fluid and independent plasmonic dual resonances

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.10.23 ◽

2019 ◽

Vol 10 ◽

pp. 247-255 ◽

Cited By ~ 9

Author(s):

Kun Ren ◽

Xiaobin Ren ◽

Yumeng He ◽

Qun Han

Keyword(s):

Magnetic Field ◽

Refractive Index ◽

Magnetic Fluid ◽

High Sensitivity ◽

Magnetic Sensors ◽

Magnetic Field Sensor ◽

Plasmonic Waveguides ◽

Coupled Mode ◽

Field Sensor ◽

Self Reference

A magnetic-field sensor with self-reference characteristic based on metal–dielectric–metal (MDM) plasmonic waveguides and a magnetic fluid (MF) is proposed and theoretically investigated. Independent dual resonances are supported by the coupled resonator–waveguide system. The physical mechanisms of dual resonances are analyzed by the temporal coupled-mode theory. The transmission response to an external magnetic field is explored by using the remarkable tunability of the refractive index of the MF. Based on the different dependence of two resonances on the external field, a magnetic-field sensor with self-reference characteristic is achieved. The magnetic-field nanosensor shows an excellent performance with a high sensitivity of 27 pm/Oe, i.e., 270 pm/mT. The proposed sensor takes advantage of the refractive-index tunability of the MF and the compactness of the MDM waveguide structure. This research may open new opportunities to design nanoscale magnetic sensors with good performance.

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