Optical Self‐Assembly of Chiral Nanostructures by a Seed Symmetry‐Breaking Effect

Abstract It has been established that assembling chiral nanostructures using a circularly polarized laser is formidable due to their symmetry mismatch. Traditionally, complex light fields or chiral precursors are considered prerequisites for optical chiral self‐assembly. Herein, an unexpected seed symmetry‐breaking (SSB) effect is reported, through which not only are chiral structures readily assembled by circularly polarized light in a controllable manner, but the physical mechanism of chiral assembly reported so far is also clarified. The SSB effect refers to a phenomenon of symmetry reduction in photo‐generated structures—the seed for ensuing structure growth—which inevitably leads to a chiral near field and the formation of resultant chiral structures. As proof of concept, the near fields as well as the process of chiral structure evolution are recorded using a low‐melting‐point film. In this particular case, laser‐induced nanoscale Rayleigh–Taylor instability (nano‐RTI) is responsible for the initial SSB. Consequently, a simple and rapid chiral structure self‐assembly method is developed, and a programmable array with a 15% peak in the circular differential scattering spectrum (CDS) is realized.