title: Linear and nonlinear optical responses influenced by broken symmetry in an array of gold nanoparticles.
abstract: An array of low-symmetry, L-shaped gold nanoparticles is shown to exhibit high sensitivity to the state of incident polarization. Small imperfections in the shape of the actual particles, including asymmetric arm lengths and edge distortions, break the symmetry attributed to an ideal particle. This broken symmetry leads to a large angular displacement of the extinction axes from their expected locations. More significantly, second-harmonic generation experiments reveal significant second-order susceptibility tensor components forbidden to the ideal symmetry.
authors.forename: Brian
authors.initials: B
authors.lastname: Canfield
authors.forename: Sami
authors.initials: S
authors.lastname: Kujala
authors.forename: Konstantins
authors.initials: K
authors.lastname: Jefimovs
authors.forename: Jari
authors.initials: J
authors.lastname: Turunen
authors.forename: Martti
authors.initials: M
authors.lastname: Kauranen