Manipulation of Nanoparticles Using Dark-Field-Illumination Optical Tweezers with Compensating Spherical Aberration

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2009,（6）
• 页码范围: 285-288
• 页数: 4页
• 语种: 英文

摘要

Based on our previous investigation of optical tweezers with dark field illumination[Chin.Phys.Lett.25(2008)329],nanoparticles at large trap depth axe better viewed in wide field and real time for a long time,but with poor forces.Here we present the mismatched tube length to compensate for spherical aberration of an oil-immersion objective in a glass-water interface in an optical tweezers system for manipulating nanoparticles.In this way,the critical power of stable trapping particles is measured at different trap depths.It is found that trap depth is enlarged for trapping nanoparticles and trapping forces are enhanced at large trap depth.According to the measurement,70-nm particles are manipulated in three dimensions and observed clearly at large appropriate depth.This will expand applications of optical tweezers in a nanometre-scale colloidal system.