Research Progress in Quantum Weak Measurement Methods for Chiral Molecule Detection

In recent years, the detection of chiral molecules has drawn significant attention due to the substantial presence of chiral drugs in the market, where different chiral forms of drugs exhibit distinct pharmacological effects or even opposing effects. Various methods for chiral molecule detection have been developed, including mass spectrometry, chromatography, sensor-based techniques, and fluorescent labeling methods. However, these methods have certain limitations such as expensive equipment, long detection times, and causing sample damage.To address these limitations, this paper introduces a novel method that combines the optical spin Hall effect with quantum weak measurement techniques for chiral molecule recognition, concentration detection, enantiomeric purity assessment, and specific rotation measurement. This approach offers advantages such as non-contact measurement and high efficiency. Currently, quantum weak measurement techniques for chiral molecules primarily rely on the optical spin Hall effect, where Light undergoes separation of different vector components during the process of reflection and transmission. By amplifying this weak value deviation through appropriate pre-selection and post-selection processes, followed by the measurement of the displacement weak value of the final measured light spot deviation, the chirality of chiral molecules can be detected.Currently, quantum weak measurement techniques for chiral molecules have been extensively researched and developed, with several applications including linear transmission type detection, prism reflection type detection, prism reflection type detection combined with metal plasmon resonance, prism reflection type detection combined with multilayer metal film technology, prism reflection type detection combined with metasurfaces, and Mach-Zehnder interferometry-based methods for selectively removing noise by choosing specific vector spectral components.