Particle manipulation beyond the diffraction limit using structured super-oscillating light beams

• 来源期刊: 光：科学与应用（英文版）
• 关键词: beam shaping optical tweezers optical vortex super-oscillating beams
• 年，卷（期）: 2017,（3）
• 页码范围: 227-232
• 页数: 6页
• 语种: 英文
• DOI: 10.1038/Isa.2017.50

摘要

The diffraction-limited resolution of light focused by a lens was derived in 1873 by Ernst Abbe.Later in 1952,a method to reach sub-diffraction light spots was proposed by modulating the wavefront of the focused beam.In a related development,super-oscillating functions,that is,band-limited functions that lecally oscillate faster than their highest Fourier component,were introduced and experimentally applied for super-resolution microscopy.Up till now,only simple Gaussian-like sub-diffraction spots were used.Here we show that the amplitude and phase profile of these sub-diffraction spots can be arbitrarily controlled.In particular,we utilize Hermite-Gauss,Laguerre-Gauss and Airy functions to structure super-oscillating beams with subdiffraction lobes.These structured beams are then used for high-resolution trapping and manipulation of nanometer-sized particles.The trapping potential provides unprecedented localization accuracy and stiffness,significantly exceeding those provided by standard diffraction-limited beams.