High-Precise Measurement of Optical Rotatory Dispersion Based on Weak Value Amplification

• Main Authors: Jingyi Shao, Lan Luo, Yu He, Jiacheng You, Yurong Liu, Yuyuan Wang, Zhiyou Zhang
• Format: Article
• Language: English
• Published: IEEE 2021-01-01
• Series: IEEE Photonics Journal
• Subjects: weak measurement; chiroptical signals; optical rotation; circular dichroism
• Online Access: https://ieeexplore.ieee.org/document/9477140/

Chiroptical signals (generally very weak) play significant roles in chiral discrimination that bring great benefits in biochemistry, pharmacy, chemical, and so on. But, high-precise chiroptical detection is still a challenge. In this paper, a high-precise measurement of optical rotatory dispersion (ORD) based on weak value amplification (WVA) is presented. We proposed ORD detection method with parameter separation: by introducing complex coupling strength and dimensionless parameter &#x201C;intensitiy contrast ratio&#x201D; pointer, the ORD is only associated with the imaginary part of the weak value while circular dichroism (CD) is only associated with the real part. By designing a suitable WVA scheme, the ORD and CD can be measured separately. In the experiment, the reliability of the parameter separation method for ORD measurement is verified, and the precision reach the order of <inline-formula><tex-math notation="LaTeX">$10^{-6}$</tex-math></inline-formula> rad. This method has a broad application prospect in biomedical sensing, medicine, chemical analysis and other fields.