Trapping Characteristic Research Of Novel Single Fiber Optical Tweezers

Fiber optical tweezers has the advantages of simple structures, cheap price, wide trapping range, and meets the experimental demand of various microscope manipulations. Based on these advantages, it is more conducive to the promotion and applications, and has been widely notated. In this thesis, two kinds of fiber optical tweezers systems have been studied: the novel single core fiber optical tweezers system—aiming to capture two micro-particles at one time; the novel two-core fiber optical tweezers—aiming to rotate the trapped micro-particles.For the novel single core fiber optical tweezers system, a particular fiber probe structure was designed. Combined the finite difference time domain method with the momentum conservation law of the electromagnetic field, the output optical field and the stress states of micro-particles were analyzed. The trapping effects of this system were also discussed under the conditions of different fiber structures, micro-particle sizes and refractive index. In the experiment, two yeast cells were successfully trapped and moved. Also, the trapped east cell trapped was further transferred in the optical trapping wells of two fiber optical tweezers. This technology is helpful to the transfer of multiple micro-particles, micro-fabrication assembling, cell fusion, etc.For the novel two-core fiber optical tweezers system, the special designed structure of the two-core fiber probe was proposed. Subsequently, the trapping principle and photo-induced rotation mechanism were analyzed by the beam propagation method. In the experiment, this fiber optical tweezers was successfully used for micro-particle trapped and rotated in 3D. This technique extends one dimensional angle operation to optical tweezers and is significant for the further improvement and application of fiber optical trapping technology.