Alignment, rotation, and spinning of single plasmonic nanoparticles and nanowires using polarization dependent optical forces.
We demonstrate optical alignment and rotation of individual plasmonic nanostructures with lengths from tens of nanometers to several micrometers using a single beam of linearly polarized near-infrared laser light. Silver nanorods and dimers of gold nanoparticles align parallel to the laser polarization because of the high long-axis dipole polarizability. Silver nanowires, in contrast, spontaneously turn perpendicular to the incident polarization and predominantly attach at the wire ends, in agreement with electrodynamics simulations. Wires, rods, and dimers all rotate if the incident polarization is turned. In the case of nanowires, we demonstrate spinning at an angular frequency of approximately 1 Hz due to transfer of spin angular momentum from circularly polarized light.
Tong
Lianming
L
Department of Applied Physics, Chalmers University of Technology, Goteborg, Sweden. lianming.tong@chalmers.se
Miljković
Vladimir D
VD
Käll
Mikael
M
D019281:Dimerization; D004563:Electrochemistry / Q000379:methods; D007834:Lasers; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry*; D049329:Nanostructures / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D043942:Nanotubes / Q000737:chemistry*; D053770:Nanowires / Q000737:chemistry*; D052898:Optical Tweezers; D055095:Optics and Photonics; D012542:Scattering, Radiation; D012834:Silver / Q000737:chemistry; D013053:Spectrophotometry / Q000379:methods
D012834:Silver