Fabricating fiber probes for optical tweezers by an improved tube etching method

An improved tube etching method to fabricate high-quality fiber probes for optical tweezers by reserving a certain length of bare fiber to form a T-type composite structure was proposed and implemented. This method can overcome the impact of fiber types on the quality of probes in the conventional tube etching effectively. Based on the influence of gravity and diffusion on the motion of reactants, the analysis of formation mechanism was proposed for this method. This procedure retained the advantage of smooth surface in traditional tube etching but shortened the etching time. Our results also demonstrated that light transmittance of the probe fabricated by this method was improved by 6.8 times, resulting in a greater force in cells trapping. This work provided a way of designing and fabricating optical fiber tweezers with a high trapping efficiency.