论文标题
表面增强的四边形布置纳米霍尔斯
Surface Enhanced Circular Dichroism by Quadrilateral Arranged Nanoholes
论文作者
论文摘要
圆形二色性（CD）是组件右手和左圆极化光的吸收差异。 CD光谱技术是检测分子手性的重要工具，但是分子圆二色性（MCD）很弱，并且总是出现在紫外线（UV）区域，该区域比视觉范围更嘈杂（VR）。引起的循环二色性（ICD）是由于等离子体纳米结构和手性分子的近场相互作用引起的，增强了分子手性的检测极限，通常出现在VR中。在这项研究中，提出了四边形布置的纳米骨（QAN）来增强MCD。结构实现的最大增强功能约为MCD的200倍。此外，我们解释了ICD的机制，该机制是通过分子偶极子对QAN的对称性破坏产生的。我们通过分析电偶极子（ED）和磁性偶极子（MD）共振模式研究了表面等离子体共振（SPR）模式对ICD的影响。由于QAN周围的ED和MD共振重叠，ICD被发现增强了。除了这项研究外，我们还探测了结构厚度，孔长度和周期长度对MCD增强的影响
Circular dichroism (CD) is absorption difference of right-hand and left-hand circularly polarized light by components. CD spectroscopy technique is an important tool for detecting molecular chirality, but the molecular circular dichroism (MCD) is weak and always appears in the ultraviolet (UV) region that is more noisy than visual range (VR). Induced circular dichroism (ICD) arisen from near-field interaction of plasmonic nanostructures and chiral molecules enhances the detection limit of molecular chirality and usually appears in VR. In this study, quadrilateral arranged nanoholes (QAN) are proposed for enhancing the MCD. The maximum enhancement achieved by the structure is about 200 folds of the MCD. Furthermore, we explained the mechanism of ICD which is generated by symmetry breaking of electric field QAN by molecular dipole. We investigated the effect of surface plasmon resonance (SPR) mode on ICD through analyzing the electric dipole (ED) and magnetic dipole (MD) resonance modes. ICD was found to get enhanced as a result of overlapping of ED and MD resonance around QAN. Besides this investigation, we probed the effects of thickness of structure, length of holes and length of periods on the MCD enhancement
