Asymmetric transmission in tunable spoof plasmonic meta-waveguide and its applications in High-Efficiency Biological Temperature Sensing and Imaging

Temperature is one of the most sensitive properties for early disease detection, especially in the current epidemic situation. High-sensitivity and flexible portable biological temperature sensors for a real-time monitor are becoming urgently reliable. Here, a tunable spoof plasmonic meta-waveguide (SPMW) is constructed to realize ultra-sensitive temperature sensing. More importantly, compared with other devices, this sensor affords visual temperature imaging, which provides the precise monitoring of large-area temperature. All these advantages are due to the ingenious configuration of spoof plasmonic meta-waveguide and material characteristics. The phase of plasma wave changes can be nearly $2 \pi$ as the $\varepsilon^{\prime}$ value of polymer-based wave-transparent material only varies ∼5%. Furthermore, the combination of 2D material, graphene, further provides impressive flexibility and robustness for the practical applications of the whole system. This finding opens an unexpected horizon for the field of ultrasensitive sensing, that points out the promising way for flexible portable wearable temperature detectors