title: Self assembled nanoparticle aggregates from line focused femtosecond laser ablation.
abstract: In this paper we present the use of a line focused femtosecond laser beam that is rastered across a 2024 T3 aluminum surface to produce nanoparticles that self assemble into 5-60 micron diameter domed and in some cases sphere-shaped aggregate structures. Each time the laser is rastered over initial aggregates their diameter increases as new layers of nanoparticles self assemble on the surface. The aggregates are thus composed of layers of particles forming discrete layered shells inside of them. When micron size aggregates are removed, using an ultrasonic bath, rings are revealed that have been permanently formed in the sample surface. These rings appear underneath, and extend beyond the physical boundary of the aggregates. The surface is blackened by the formation of these structures and exhibits high light absorption.
authors.affiliation: Department of Electrical Engineering, University of Nebraska Lincoln, 844 N 16th St Lincoln, NE 68588, USA.
authors.forename: Craig A
authors.initials: CA
authors.lastname: Zuhlke
authors.forename: Dennis R
authors.initials: DR
authors.lastname: Alexander
authors.forename: John C
authors.initials: JC
authors.lastname: Bruce
authors.forename: Natale J
authors.initials: NJ
authors.lastname: Ianno
authors.forename: Chad A
authors.initials: CA
authors.lastname: Kamler
authors.forename: Weiqing
authors.initials: W
authors.lastname: Yang