Farrokhfar Motahhare, Jarchi Saughar, Keshtkar Asghar
Appl Opt. 2021 Mar 10;60(8):2434-2440. doi: 10.1364/AO.418041.
A periodic planar metamaterial sensor in the terahertz band based on surface plasmon polariton resonances is proposed and studied. The unit cell includes four half-elliptical graphene rings located on a three-layer substrate including a layer, an air gap, and another layer. The embedded air gap between the two layers of improves the sensitivity of the sensor. Parametric study is performed, and the effects of the dimensions of the elliptical rings, the air gap thickness, and the Fermi energy of graphene on resonant frequency, sensitivity, and figure of merit (FoM) are investigated and graphically illustrated. The parameters of the sensor are optimized to provide a high sensitivity with a suitable FoM. By changing the refractive index of the sensing environment from 1.2 to 2, maximum sensitivity of 21.1 µm/RIU with FoM 5.14 is provided. The performance of the sensor is compared with previous works, and it is shown that a considerable improvement in sensitivity is achieved. The proposed sensor is suitable for biosensing applications.
提出并研究了一种基于表面等离激元极化激元共振的太赫兹波段周期性平面超材料传感器。该单元胞包括位于三层衬底上的四个半椭圆形石墨烯环，三层衬底包括一层、一个气隙和另一层。两层之间嵌入的气隙提高了传感器的灵敏度。进行了参数研究，研究了椭圆环尺寸、气隙厚度和石墨烯费米能量对共振频率、灵敏度和品质因数（FoM）的影响，并以图形方式进行了说明。对传感器参数进行优化以提供具有合适品质因数的高灵敏度。通过将传感环境的折射率从1.2改变到2，可提供21.1 µm/RIU的最大灵敏度，品质因数为5.14。将该传感器的性能与先前的工作进行了比较，结果表明灵敏度有了显著提高。所提出的传感器适用于生物传感应用。
