在固態物理學中，一個週期性的晶格是以晶胞為單位，組成不同種類的布拉維晶格，我們亦可分配晶胞的排列和布拉格晶格來組成給定的金屬週期結構。本論文中，我們展示了500nm粒子在電漿子增強的二維方形光晶格中，改變極化方向時的運輸特性，其光晶格位勢便是將高斯雷射光束打入週期性的金奈米圓盤陣列來激發雷射共振。
實驗上，500nm的螢光小球被滴至於樣品中，並使用螢光成像的CCD相機記錄其運動行為，最後使用Matlab程式匯出影像的軌跡。我們蒐集了約180條在不同入射光強度的粒子軌跡來做分析，粒子軌跡可以在合適的粒子大小，位勢深度及週期式位勢配合的情況下機率性的鎖定在特定的通道內，其中，最突出的通道方向為[01]、[10]、[11]。

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].

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