The dissymmetry factor of the experimentally optimized structures reached values of up to ∼1.03, which is much larger than other nano-plasmonic systems of the same order of dimension. The dependence of the plasmon coupling and dissymmetry factor on the gap size and twisted angle clearly demonstrates that the plasmon coupling followed by the hybridization strongly enhances the chiroptical response. To this end, we realize the fabrication of twisted nanorods with a small gap size of ∼15 nm to ensure that we can observe the separated hybridized modes generated by the plasmon coupling between the twisted nanorods. Here, we extend the study of chiroptical response concerning the interaction between the constituents to a strong plasmon coupling regime based on the dimer of twisted metal nanorods. Note that the interaction between the constituents is extremely important and indispensable to the chiroptical response in a chiral plasmonic system. Recently, chiral plasmonic structures have received significant attention because of their large chiroptical response. The chiroptical response of most naturally occurring chiral materials is generally very weak, which discourages further studies and limits applications.

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