Double-parameter analysis of an asymmetric herringbone temperature and refractive index sensor based on...

The all-dielectric metasurface is a tremendously efficacious path to seek out planar optical manipulators. The application of extremely sensitive optical sensors is expected to benefit from the Fano resonances created in all-dielectric metasurface. An optical sensor basaed on the all-dielectric hollow herringbone metasurface is tuned for high-sensitivity temperature sensing and refractive index sensing. In the continuous near-infrared band, two resonance responses activated by magnetic toroidal dipole and magnetic quadrupole can be generated simultaneously. According to the simulation results, a superior properties refractive index sensor holding a Q factor as high as 2.6 × 10⁴ is achieved, its maximum FOM of 3980 RIU^-1 is displayed, and its sensitivity is 232 nm/RIU. And sensitivity of the temperature sensor is proved to be 63 pm/K, which shows a prominent improvement in temperature sensing. After analyzing it in the experiment, it is found that the Q factor is 5366 and FOM of 465 RIU^-1, with the sensitivity of 178 nm/RIU. This refractive sensor provides a favorable groundwork for developing high-sensitivity sensing devices in many biochemical disciplines, which also increases the extensive application possibilities for biochemical analysis and environmental detection.