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

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 1mW/mu 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. (c) 2022 Optica Publishing Group