激光捕获技术及其发展

激光捕获技术是利用光辐射力来捕捉、移动和操纵微粒的先进技术。光镊即单光束梯度力光阱是通过在高度会聚的激光束束腰附近所产生的极高的场强梯度来形成皮牛顿量级的力,可以三维地捕获和操纵微小粒子。阐述了激光捕获技术的模型和原理以及系统的基本结构;追踪了激光捕获技术的最新研究进展;介绍了非高斯型光阱、光纤光阱和全息光镊等几种特殊形式,并分析了每种形式的特点。展望了激光捕获技术的发展前景。

Principles and development of laser trapping technique

Laser trapping is an advanced technique that utilizes radiation force to capture,translate and manipulate microscopic particles.Optical tweezers,also known as single beam gradient force optical trap,rely upon the extremely high gradient in the electric field produced near the beam waist of a highly focused laser beam,which creates Pico-Newton force sufficient enough to trap small particles in three dimensions.The models and principles of laser trapping technique are reviewed.The basic system setup is introduced.Various novel approaches of laser trapping,such as non-Gaussian optical trap,fiber optical trap and holographic tweezers,are described respectively.The characteristics of each approach are analyzed.The prospects for further development are discussed.