title: Transfer of light helicity to nanostructures.
abstract: We discovered that chiral nanoneedles fabricated by vortex laser ablation can be used to visualize the helicity of an optical vortex. The orbital angular momentum of light determines the chirality of the nanoneedles, since it is transferred from the optical vortex to the metal. Only the spin angular momentum of the optical vortex can reinforce the helical structure of the created chiral nanoneedles. We also found that optical vortices with the same total angular momentum (defined as the sum of the orbital and spin angular momenta) are degenerate, and they generate nanoneedles with the same chirality and spiral frequency.
authors.affiliation: Graduate School of Advanced Integration Science, Chiba University, Chiba 263-8522, Japan.
authors.forename: Kohei
authors.initials: K
authors.lastname: Toyoda
authors.affiliation: Graduate School of Advanced Integration Science, Chiba University, Chiba 263-8522, Japan.
authors.forename: Fuyuto
authors.initials: F
authors.lastname: Takahashi
authors.affiliation: Graduate School of Advanced Integration Science, Chiba University, Chiba 263-8522, Japan.
authors.forename: Shun
authors.initials: S
authors.lastname: Takizawa
authors.affiliation: Graduate School of Advanced Integration Science, Chiba University, Chiba 263-8522, Japan and Japan Science and Technology Agency, CREST, 5 Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Yu
authors.initials: Y
authors.lastname: Tokizane
authors.affiliation: Graduate School of Advanced Integration Science, Chiba University, Chiba 263-8522, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Miyamoto
authors.affiliation: Department of Applied Physics, Hokkaido University, Sapporo 060-8628, Japan and Japan Science and Technology Agency, CREST, 5 Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Ryuji
authors.initials: R
authors.lastname: Morita
authors.affiliation: Graduate School of Advanced Integration Science, Chiba University, Chiba 263-8522, Japan and Japan Science and Technology Agency, CREST, 5 Sanbancho, Chiyoda-ku, Tokyo 102-0075, Japan.
authors.forename: Takashige
authors.initials: T
authors.lastname: Omatsu