Parallel trapping of multiple nanoparticles using a quasi-bound state in the continuum mode

Abstract

In this work, we put forward an all-dielectric nanotweezer using a quasi-bound state in the continuum (quasi-BIC) mode to trap nanoparticles with a radius of 10 nm. The quasi-BIC mode provides not only a very high electric field enhancement but also a high quality factor ( Q -factor), which gives it potential for the trapping of nanoparticles with low laser power and high stability. The simulation results show that when the input intensity is 1 m W / µ m 2 , the maximum optical trapping force of the 10 nm particles is 2.24 pN, and the maximum trapping potential is 29.08 k B T . Furthermore, the proposed nanotweezer array provides multiple optical hotspots with high field confinement and enhancement, resulting in multiple trapping sites for the parallel trapping of multiple nanoparticles. The high-throughput trapping of nanoparticles provides a good foundation for studying biological cells and protein molecules, especially for the heterogeneity of cells and the large-scale parallel analyses of basic drugs.