Sculpting Light with Plasmon: Nanoemitter, Superchirality, and Discriminatory Optical Force

Sculpting light at nanoscale signifies a substantial step towards comprehensively manipulate the interactionbetween light and molecules. To date, properties of light such as wavelength, intensity, and phase can beeasily tailored via the interaction with collective oscillation of electrons, namely plasmon, which is nearlydiffraction unlimited. However, being capable of modulating the polarization state at nanoscale at one’sdesire is still challenging and is widely believed as the last mile to fully control and enhance the interactionsbetween photons and the transition dipoles of molecules. Just as the famous remark:“Polarized light is the most subtle and delicate investigator of molecular condition.” By Michael Faraday.In this 3-year-project, we plan to establish a broadband wavelength tunable nanoemitter with controllablepolarization state, study the superchiral phenomenon for chirality recognition, and synthesize discriminatoryoptical force for enantiomer separation. The main methodologies employed in this project include 1. Thefabrication of plasmon trimers, 2. Superresolved four wave mixing spectroscopy/microscopy, 3. Conicalrefraction based polarimetry, 4. Generalized multiparticle Mie (GMM) simulation, and 5. Opto-fluidicstechnologies. Technique 1 & 2 are existing home-built technologies based on which, relevant papers arepublished. For technique 3 & 4, we have done the simulation and the predicted results have been obtained.We will then focus on the construction of the experimental platform to verify the predictions in this project.For technique 5, preliminary result on the propelling of dielectric and metallic spheres using optical force hasbeen obtained. In this project, we will integrate functionalities to achieve chiral recognition and enantiomerseparation simultaneously. To improve the power stability and mitigate the deadly thermal effect, we requesta pumping laser and a cryostat. It is hoped that with the requested instrument support, the experimentalcondition and environmental control can be largely improved. Were the abovementioned targets successful,the results will certainly benefit to the scientific society, especially for the field of bio-labeling,nano-medicinal molecular chirality identification, and enantiomer separation.