2019/11/30 by Xionggui Tang, Tang, Xionggui, Fan Nan +3
Engineering · Physics and Astronomy · #Advanced Fiber Laser Technologies #FOS: Physical sciences #Instrumentation and Detectors (physics.ins-det) #Optics (physics.optics) #Orbital Angular Momentum in Optics #Photonic and Optical Devices
paper · pdf · doi:10.48550/arxiv.1912.00218
openalex publication_date 2019/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Conventional optical tweezers are generated by the intensity gradient of highly focused laser beams, but the requirement of strong intensity gradient limits the tunability of optical traps. Here we show a new type of optical tweezers with tunable potential wells by manipulating the phase gradient of light. Using a new method to calculate holograms, we can design desirable phase profiles and intensity distributions of optical patterns. Optical force arising from the phase gradient creates tunable potential wells for versatile optical manipulation, such as trapping nanoparticles in peanut-shaped optical spots, and positioning and shifting nanoparticles in optical gears as demonstrated in our experiments. The phase-gradient-based optical tweezers have several merits including flexible design and easy control, which open a new way for optical trapping and manipulation.