High-Sensitivity Detection for Kidney Cancer Cells Using Polarization Insensitive EIT-Like THZ Metasurface Biosensor

This paper numerically calculated and experimentally verified a high sensitivity terahertz polarization insensitive electromagnetically induced transparency-like (EIT-like) metasurface sensor. Compared the state of art, the transparency peak of the proposed sensor is not only polarization insensitive but also has a high sensitivity <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(S)$</tex> of 0.321 THz/RIU and a high mean sensitivity <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(S_{mean})$</tex> of 0.237 RIU<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup>. The experiment not only fully proves the polarization insensitive and the robustness of the proposed metasurface but also the ability of the proposed sensor for quickly quantitative detection of living kidney cancer cells (<tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0,\ 2\times 10^{5}$</tex> and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$8\times 10^{5}$</tex> cells/mL) based on two degrees of variations, including the dip/peak frequency shift <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\Delta f)$</tex> and amplitude attenuation <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$(\Delta A)$</tex>. This work is of great significance for the rapid diagnosis and early screening of kidney cancer in the field of THz biosensing.