Lu Jinsheng, Ginis Vincent, Lim Soon Wei Daniel, Capasso Federico
Harvard John A. Paulson School of Engineering and Applied Sciences, 9 Oxford Street, Cambridge, Massachusetts 02138, USA.
Data Lab and Applied Physics, Vrije Universiteit Brussel, 1050 Brussel, Belgium.
Phys Rev Lett. 2023 Oct 6;131(14):143803. doi: 10.1103/PhysRevLett.131.143803.
Optical traps using nonconservative forces instead of conservative intensity-gradient forces expand the trap parameter space. Existing traps with nonconservative helicity-dependent forces are limited to chiral particles and fields with helicity gradients. We relax these constraints by proposing helicity and polarization gradient optical trapping of achiral particles in evanescent fields. We further propose an optical switching system in which a microsphere is trapped and optically manipulated around a microfiber using polarization gradients. Our Letter deepens the understanding of light-matter interactions in polarization gradient fields and expands the range of compatible particles and stable trapping fields.
使用非保守力而非保守强度梯度力的光阱扩展了阱参数空间。现有的具有非保守螺旋度相关力的光阱仅限于手性粒子和具有螺旋度梯度的场。我们通过提出在倏逝场中对非手性粒子进行螺旋度和偏振梯度光阱来放宽这些限制。我们还提出了一种光学切换系统，其中使用偏振梯度在微光纤周围捕获并光学操纵微球。我们的论文加深了对偏振梯度场中光与物质相互作用的理解，并扩展了兼容粒子和稳定捕获场的范围。
