Researchers routinely sense molecules by their infrared vibrational "fingerprint" absorption resonances. In addition, the dominant handedness of chiral molecules can be detected by circular dichroism (CD), the normalized difference between their optical response to incident left- and right- handed circularly polarized light. Here, we introduce a cavity composed of two parallel arrays of helicity-preserving silicon disks that allows one to enhance the CD signal by more than 2 orders of magnitude for a given molecule concentration and given thickness of the cell containing the molecules. The underlying principle is first-order diffraction into helicity-preserving modes with large transverse momentum and long lifetimes. In sharp contrast, in a conventional Fabry-Perot cavity, each reflection flips the handedness of light, leading to large intensity enhancements inside the cavity, yet to smaller CD signals than without the cavity.

中文翻译：

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保留螺旋性的光学腔模式，用于增强手性分子的传感。

研究人员通常通过其红外振动“指纹”吸收共振来感知分子。此外，手性分子的主要惯用性可以通过圆二色性（CD）来检测，圆二色性是它们对入射的左旋和右旋圆偏振光的光学响应之间的归一化差异。在这里，我们介绍了一个空腔，该空腔由两个平行排列的保螺旋性硅盘组成，对于给定的分子浓度和给定的包含该分子的单元的厚度，该盘可以使CD信号增强2个数量级以上。基本原理是一阶衍射到具有大横向动量和长寿命的保螺旋性模式中。与之形成鲜明对比的是，在传统的Fabry-Perot腔中，每次反射都会使光的手感翻转，