Elvira Iris, Muñoz-Martínez Juan F, Barroso Álvaro, Denz Cornelia, Ramiro José B, García-Cabañes Angel, Agulló-López Fernando, Carrascosa Mercedes
Opt Lett. 2018 Jan 1;43(1):30-33. doi: 10.1364/OL.43.000030.
Optical tools for manipulation and trapping of micro- and nano-objects are a fundamental issue for many applications in nano- and biotechnology. This work reports on the use of one such method, known as photovoltaic optoelectronics tweezers, to orientate and organize cylindrical microcrystals, specifically elongated zeolite L, on the surface of Fe-doped LiNbO crystal plates. Patterns of aligned zeolites have been achieved through the forces and torques generated by the bulk photovoltaic effect. The alignment patterns with zeolites parallel or perpendicular to the substrate surface are highly dependent on the features of light distribution and crystal configuration. Moreover, dielectrophoretic chains of zeolites with lengths up to 100 μm have often been observed. The experimental results of zeolite trapping and alignment have been discussed and compared together with theoretical simulations of the evanescent photovoltaic electric field and the dielectrophoretic potential. They demonstrate the remarkable capabilities of the optoelectronic photovoltaic method to orientate and pattern anisotropic microcrystals. The combined action of patterning and alignment offers a unique tool to prepare functional nanostructures with potential applications in a variety of fields such as nonlinear optics or plasmonics.
用于操纵和捕获微米及纳米物体的光学工具是纳米技术和生物技术中许多应用的一个基本问题。这项工作报道了一种此类方法的应用，即光伏光电子镊子，用于在掺铁铌酸锂晶体板表面上对圆柱形微晶（特别是细长的L型沸石）进行定向和排列。通过体光伏效应产生的力和扭矩实现了对齐的沸石图案。沸石与基板表面平行或垂直的排列图案高度依赖于光分布和晶体构型的特征。此外，经常观察到长度达100μm的沸石介电泳链。讨论了沸石捕获和排列的实验结果，并与倏逝光伏电场和介电泳势的理论模拟进行了比较。它们展示了光电子光伏方法对各向异性微晶进行定向和图案化的卓越能力。图案化和排列的联合作用提供了一种独特工具，可用于制备在诸如非线性光学或等离子体学等各种领域具有潜在应用的功能性纳米结构。
