Baghbadorani H Kaviani, Barvestani J, Entezar S Roshan
Appl Opt. 2017 Jan 20;56(3):462-469. doi: 10.1364/AO.56.000462.
In biosensors research, much effort has been made to achieve high sensitivity to detect lower concentrations of analyte in a solution by testing different kinds of materials. In this paper, we present a biosensor based on Bloch surface waves made of photonic crystal (PhC) including graphene nanolayers under the Kretschmann configuration. The band structures, surface modes, reflectivity, and sensitivity of the PhC biosensor are calculated by the transfer matrix method and results are compared with those of the structure without graphene layers. Our investigations show that the angular sensitivity of the biosensor considerably increases in the presence of the graphene layers. Moreover, we study the effect of the number of the graphene layers placed on the surface of the biosensor on the performance of our proposed biosensor. The results reveal that the sensitivity of the biosensor is enhanced by increasing the number of graphene layers on the surface due to the π-stacking interactions between graphene's honeycomb cells and the carbon rings in biomolecules. Furthermore, our results show that the phase sensitivity is higher than the angular sensitivity, which can promote the accuracy of the calculations.
在生物传感器研究中，人们通过测试不同种类的材料，付出了诸多努力以实现高灵敏度，从而检测溶液中更低浓度的分析物。在本文中，我们展示了一种基于光子晶体（PhC）的布洛赫表面波生物传感器，该光子晶体包括处于Kretschmann配置下的石墨烯纳米层。通过传输矩阵法计算了光子晶体生物传感器的能带结构、表面模式、反射率和灵敏度，并将结果与没有石墨烯层的结构的结果进行了比较。我们的研究表明，在存在石墨烯层的情况下，生物传感器的角度灵敏度显著提高。此外，我们研究了放置在生物传感器表面的石墨烯层数对我们所提出的生物传感器性能的影响。结果表明，由于石墨烯蜂窝单元与生物分子中的碳环之间的π-堆积相互作用，通过增加表面石墨烯层数可提高生物传感器的灵敏度。此外，我们的结果表明相位灵敏度高于角度灵敏度，这可以提高计算的准确性。
