Highly sensitive sensors of fluid detection based on magneto-optical optical Tamm state

We propose a new magneto-optical optical Tamm state (MOOTS) sensor in fluid detection. The device consists of a dielectric magneto-optical thin film of Ce-doped Y3Fe5O12 (CeYIG), a metallic film of Ag and a periods of the distributed Bragg reflector (DBR). Finite element method (FEM) and 4 × 4 transfer matrix method are employed to calculate the figure of merit (FOM) of sensitivity. Calculation results indicate that a FOM of 1224.21/RIU for gas refractive index variation from 1.0000 to 1.0006 can be obtained when the incident wavelength is 1064 nm, which is much larger than the FOM of magneto-optical surface plasmon resonance (MOSPR) device. Meanwhile, our MOOTS sensor is insusceptible to the influence of smoothness of the interface of deposited layers and can provide the great error tolerance, which is more conducive to the manufacture, production and actual performance. In addition, the experiment route to detect the refractive index of air and NaCl solution has been revealed.