METHOD FOR TUNABLE LIGHT BITRAP SHAPING

Abstract

We developed a method for tunable light bitrap shaping meant for a simultaneous manipulation of two particles. The method is based on the light bibeam with a tunable angle between propagation directions of its components. We proposed, assembled, and tested experimentally an optical scheme for realization of the method. The method is suitable for the transformation of powerful laser radiation because all optical elements in the scheme have high light beam strength. The method is very effective since light energy losses occur only during reflections on input and output sides of optical elements. These losses can be reduced to a fraction of a percent by an anti-reflecting coating for the used wavelength on the sides of optical elements. The possibility of an energy redistribution between trap peaks permits one to conduct effectively with a pair of microparticles having different refraction indices and sizes. Light intensity maxima of the shaped bipeak light field are microscopic in size, since it can be used not only for manipulation of micron and submicron particles, but for high-resolution microscopy, for nondestructive testing of a coating thickness, and for precision laser processing of materials, including metals.