@article{oai:oist.repo.nii.ac.jp:00001833,
 author = {Bouloumis, Theodoros D and Kotsifaki, Domna G and Han, Xue and Chormaic, Síle Nic and Truong, Viet Giang},
 issue = {2},
 journal = {Nanotechnology},
 month = {Oct},
 note = {The manipulation of microparticles using optical forces has led to many applications in the life and physical sciences. To extend optical trapping towards the nano-regime, in this work we demonstrate trapping of single nanoparticles in arrays of plasmonic coaxial nano-apertures with various inner disk sizes and theoretically estimate the associated forces. A high normalized experimental trap stiffness of 3.50 fN nm⁻¹ mW⁻¹ μm⁻² for 20 nm polystyrene particles is observed for an optimum design of 149 nm for the nanodisk diameter at a trapping wavelength of 980 nm. Theoretical simulations are used to interpret the enhancement of the observed trap stiffness. A quick particle trapping time of less than 8 s is obtained at a concentration of 14 x 10¹¹ particles ml⁻¹ with low incident laser intensity of 0.59 mW μm⁻². This good trapping performance with fast delivery of nanoparticles to multiple trapping sites emerges from a combination of the enhanced electromagnetic near-field and spatial temperature increase. This work has applications in nanoparticle delivery and trapping with high accuracy, and bridges the gap between optical manipulation and nanofluidics.},
 title = {Fast and efficient nanoparticle trapping using plasmonic connected nanoring apertures},
 volume = {32},
 year = {2020}
}