TY - JOUR

T1 - Principles of Measuring Thickness and Refractive Index of Thin Dielectric Film by Using Multiresonance Archimedean Spiral Metasurfaces with C Resonator in the Terahertz Frequency Range

AU - Kameshkov, Oleg

AU - Gerasimov, Vasily

PY - 2024

Y1 - 2024

N2 - Metasurfaces are an excellent platform for terahertz (THz) sensing applications, enabling highly efficient light–matter interaction and overcoming the fundamental disadvantage of the relatively long-wavelength THz range (30–3000 μm), which limits sensing of small features. The current focus in developing metasurfaces is mostly directed toward single-resonance metasurfaces and reconstruction of the dielectric constants of analyte from the saturation mode induced by the limited sensing volume of the metasurface. This paper presents a numerical demonstration of using a multiresonance metasurface to extract the thickness and refractive index of a deposited film without saturation of the sensor. It was shown that the multiresonance property enables determination of the analyte characteristic via measurements with two different thicknesses and tracking changes in two resonances. High-accuracy parameter retrieval is achieved when there are large differences in the thicknesses. In contrast to the established approach, this method provides an efficient way to avoid using relatively thick films.

AB - Metasurfaces are an excellent platform for terahertz (THz) sensing applications, enabling highly efficient light–matter interaction and overcoming the fundamental disadvantage of the relatively long-wavelength THz range (30–3000 μm), which limits sensing of small features. The current focus in developing metasurfaces is mostly directed toward single-resonance metasurfaces and reconstruction of the dielectric constants of analyte from the saturation mode induced by the limited sensing volume of the metasurface. This paper presents a numerical demonstration of using a multiresonance metasurface to extract the thickness and refractive index of a deposited film without saturation of the sensor. It was shown that the multiresonance property enables determination of the analyte characteristic via measurements with two different thicknesses and tracking changes in two resonances. High-accuracy parameter retrieval is achieved when there are large differences in the thicknesses. In contrast to the established approach, this method provides an efficient way to avoid using relatively thick films.

KW - multiresonance

KW - sensor

KW - spoof localized surface plasmon resonance

KW - terahertz range

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85197173733&origin=inward&txGid=93246e128f6bb8e4b29f5bd7c168258b

UR - https://www.mendeley.com/catalogue/5d91bf4d-e83e-3845-96fa-93a7d2bc4a48/

U2 - 10.3390/photonics11060529

DO - 10.3390/photonics11060529

M3 - Article

VL - 11

JO - Photonics

JF - Photonics

SN - 2304-6732

IS - 6

M1 - 529

ER -