In this work, transverse optical vortices with phase singularities and orbital angular momentum are generated by the interference of three linearly polarized lights. The positions of the transverse optical vortices can be regulated by the relative amplitude and initial phase of the three incident lights. An analytical model is built for control the positions of the generated vortices and its correctness is proved by FDTD simulation, and a method for judging the positive or negative topological charge of the transverse vortices is derived. Based on the Poynting vector distribution of the transverse vortex field, it is found that there is an inverse energy flow near the phase singularity, that is, Poynting vector points to the light source rather than the propagation direction. It is further found that the controllable singularities and the backward energy flow region of the vortex field are very sensitive to the scattering of nanoparticles. When a single metal nanoparticle is placed in the region, several singularity lines with specific directions can be found in the scattering field. By changing the relative position of the single metal nanoparticle to the singularity in nanoscale, the directions of the singularity lines can be modulated. This work realizes the generation and manipulation of transverse optical vortices, and reveals the interaction between the transverse phase singularity and the scattering of metal nanoparticles, which is expected to be applied to nanoscale displacement sensing for nanoparticles.
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