Development of nano-structure fabrication by laser manipulation

利用激光束操纵小粒子作为一种构造小物体的新尝试，引起了人们的广泛关注。在这种情况下，本研究旨在建立利用光捕获技术制造微纳米尺度物体的纳米结构的新概念和基本技术。首先，开发了一种同时捕获多个单分散赤铁矿颗粒的排列技术。用线性聚焦激光束观察到粒子排列成直线而不开口。这种安排是稳定的，可以自由移动。虽然已知这些小颗粒自然粘附，但证明了静电和/或范德华力难以实现的特殊排列是通过光学捕获实现的。其次，两个粒子之间的力是通过使用两束激光独立捕获的。结果与DLVO理论吻合较好。本研究中建立的小颗粒排列技术是通过一种主动的光捕获方法实现的。人们认为这种技术对制造小物体很有用。结果还表明，两个粒子之间的自然作用力可以用DLVO理论很好地解释。我们相信我们的研究结果对未来纳米尺度物体的制造是非常有用的。

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.