Abstract
In solid state physics, a periodic crystal consists of a Bravais lattice and a unit cell. We can assign a Bravais lattice and a unit cell for a given metallic periodic nanostructures.We report the characterization of transport of 500 nm nanospheres in a plasmon-enhanced, polarization controlled two-dimensional square lattice. The optical potential is created by illuminating an array of gold nanodisks with a Gaussian beam to excite plasmon resonance. To characterize the particle trajectory in a quantitative way, we have collected more than ~180 trajectories at different incident light intensity. Fluorescently labeled nanospheres of 500 nm is dispensed on the sample and the motion is recorded by fluorescent imaging with the CCD camera. A custom Matlab program is then used to adjust the threshold of the image and extract the particle trajectory data. We observe weak kinetic locked in with most prominent "channeling" direction along directions of [01],[11],and [10].