论文标题
信号逆转的介电元面中的绝对手性传感
Absolute chiral sensing in dielectric metasurfaces with signal reversals
论文作者
论文摘要
纳米级的传感分子手性由于固有的手势信号的本质弱性质而成为一个长期的挑战，而纳米光学方法在访问这些信号方面已证明富有成果。但是，在大多数情况下，完全手性折射率的绝对手性感觉是不可能的，而来自纳米结构本身的强固有信号掩盖了弱的手势信号。在这里，我们提出了一个介电交流系统，该系统克服了这些局限性并允许绝对测量总的手性，以及重要的信号反转的可能性，可以实现手性测量而无需去除样品。作为原则的证明，我们在均匀且可接近的区域上的超薄，亚波长，手性样品的信号增强倍数为200倍。
Sensing molecular chirality at the nanoscale has been a long-standing challenge due to the inherently weak nature of chiroptical signals, and nanophotonic approaches have proven fruitful in accessing these signals. However, in most cases, absolute chiral sensing of the total chiral refractive index has not been possible, while the strong inherent signals from the nanostructures themselves obscure the weak chiroptical signals. Here, we propose a dielectric metamaterial system that overcomes these limitations and allows for absolute measurements of the total chirality, and the possibility for a crucial signal reversal that enables chirality measurements without the need for sample removal. As proof of principle, we demonstrate signal-enhancements by a factor of 200 for ultrathin, sub-wavelength, chiral samples over a uniform and accessible area.
