title: Effects of asymmetric nanostructures on the extinction difference properties of actin biomolecules and filaments.
abstract: In this paper, symmetric and asymmetric tapering on the arms of the gammadion nanostructure is proposed to enhance both local field distribution and extinction difference (ED). The asymmetric tapered gammadion with tapering fraction (TF) of 0.67 is seen to have the largest ED and spatial local field distribution, producing a large wavelength shift of more than 50 percent as compared to the untapered gammadion nanostructures when immersed in a solution of actin molecules and filaments. The optical chirality, ζ shows that the larger local field amplitudes produced by the asymmetric designs increases the rate of chiral molecules excitation. This enhanced field is strongly rotating and highly sensitive to single molecules and larger filaments. Here, we show that the ED, optical chirality, sensitivity and rate of chiral molecules excitation can be improved by incorporating asymmetric designs into chiral gammadion nanostructures through tapering.
authors.affiliation: Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, #16-16 Connexis, Singapore 138632, Singapore.
authors.forename: E H
authors.initials: EH
authors.lastname: Khoo
authors.affiliation: Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Eunice S P
authors.initials: ES
authors.lastname: Leong
authors.affiliation: Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 3 Research Link, Singapore 117602, Singapore.
authors.forename: S J
authors.initials: SJ
authors.lastname: Wu
authors.affiliation: Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, #16-16 Connexis, Singapore 138632, Singapore.
authors.forename: W K
authors.initials: WK
authors.lastname: Phua
authors.affiliation: Institute of High Performance Computing, Agency for Science, Technology and Research (A*STAR), 1 Fusionopolis Way, #16-16 Connexis, Singapore 138632, Singapore.
authors.forename: Y L
authors.initials: YL
authors.lastname: Hor
authors.affiliation: Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR), 3 Research Link, Singapore 117602, Singapore.
authors.forename: Y J
authors.initials: YJ
authors.lastname: Liu
mesh_terms: D000199:Actins / Q000737:chemistry; D002942:Circular Dichroism; D003599:Cytoskeleton / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry; D055503:Protein Multimerization; D013057:Spectrum Analysis / Q000379:methods
chemical_list: D000199:Actins