Single-Fiber Probe Fabricated By Chemical Etching To Trapping Multiple Particles

Optical tweezer is a technology that uses the radiation pressure of light to capture and manipulate micro-particles.It has the advantages of no-contact,no-damaging,high precision,and is widely used in many scientific fields such as medicine,biology,physics,effectively promoting the development of related fields.The technology of optical tweezers is developing in the direction of multi-traps optical tweezers.The double-tapered optical fiber tweezers can not only have the advantages of high precision and flexible operation,but also construct multiple optical traps,can be applied to cell surgery and precision machining and so on.In this paper,an optical fiber probe with a large double-tapered angle was fabricated by the interface layer etching method.The outgoing light field of the probe and the force on the particles were calculated by the finite element method,the capture of multiple particles chain structures and triangular structure was experimentally realized,the capture force was also measured.In this paper,the background and application of optical tweezers technology are first introduced,then the development status of multi-optical trap optical tweezers and the principles of several multi-traps optical tweezers are introduced,then the principle of optical tweezers trapping microparticles was introduced by analyzing the force on the particles.Next,interfacial layer etching method was introduced,and a primary tapered-angle fiber probe with good surface morphology was fabricated by chemical etching.The fabrication principle and operation steps of forming a secondary taper angle fiber probe by the interfacial layer etching method are introduced.Three fiber probes with a small-angle primary taper angle and a large-angle secondary taper angle are fabricated by the interfacial layer etching method.Then,the double-tapered optical fiber probes were made by interfacial layer etching method,the outgoing light field of these probes are calculated using the finite element method,the possibility of multiple optical traps was analyzed according to the distribution of the optical field intensity of the probe emission light field and its gradient,the forces on the multi-particles arranged in chains on the optical axis are calculated,the effect of the double-tapered angle and the number of particles in the chain was investigated,the effect of the refocusing and backscattering of beams by particles in multi-particle capture was also analyzed.Finally,a single-fiber optical tweezers system was built using the double-tapered optical fibers.The structure captures multi-particles,and the trapping force of the quadratic cone angle probe with different angles on the silica spheres was measured by the escape method,and the effect of the probe tilt angle on the trapping force was studied.The use of single-fiber optical tweezers composed of double-tapered optical fibers to capture multi-particles can be applied to cell surgery and micro-nano manufacturing.Interdisciplinary research and development in multiple scientific fields.