Development of nano-structure fabrication by laser manipulation

利用激光束操纵微小粒子作为一种构造微小物体的新尝试，正引起人们的广泛关注。在此背景下，本研究旨在建立基于光阱技术的微纳米结构制造新概念和基础技术。首先，发展了一种同时捕获多个单分散赤铁矿颗粒的技术。通过线性聚焦的激光束观察到，颗粒排列成直线而没有开口。这种布置是稳定的，并且可以自由移动。尽管已知这些小颗粒自然地粘附，但已经证明通过光捕获实现了通过静电和/或货车德瓦尔斯力难以实现的特殊排列。二次粒子间的力，是用两束激光独立捕获的两个粒子间的力。实验结果与DLVO理论符合较好，本研究所建立的小颗粒排列技术是通过主动光阱方法实现的。据认为，这种技术是有用的，以制造小物体。同时也证明了DLVO理论能很好地解释两个粒子之间的自然作用力。我们相信，我们的研究结果可能是非常有用的，在未来的纳米尺度物体的制造。

Manipulation of small particles by using the laser beam is attracting considerable attention as a novel attempt constructing small objects. Under these circumstances, this study have aimed at establishing new concept and basic technology of nano-structure fabrication using the optical trapping technique for micro or nanometer scale objects.First of all, a technique was developed to arrange plural monodisperse hematite particles that were simultaneously trapped. It was observed that the particles were arranged in line without opening by a linearly focused laser beam. This arrangement was stable and can be freely moved. Although these small particles are known to cohere naturally, it was demonstrated that special arrangement that is difficult by electrostatic and/or van der Waals force is achieved by the optical trapping. Secondary, forces between two particles that were optically trapped independently by using two laser beams. The result showed good agreement with DLVO theory.The arrangement technique of small particles established in this study is achieved by an active method of the optical trapping. It is thought that this technique is useful to fabricate small objects. It was also demonstrated that the naturally acting force between two particles is well explained by the DLVO theory. We believe that our results may be very useful for the fabrication of nanometer scale objects in the future.