LAUSR

We theoretically propose blue-detuned optical trapping for neutral atoms via strong near-field interfacing in a plasmonic nanohole array. The optical field at resonance forms a nanoscale-trap potential with an FWHM of 200 nm and about ∼370  nm away from the nanohole; thus, a stable 3D atom trapping independent of the surface potential is demonstrated. The effective trap depth is more than 1 mK when the optical power of trapping light is only about 0.5 mW, while the atom scattering rate is merely about 3.31  s−1, and the trap lifetime is about 800 s. This compact plasmonic structure provides high uniformity of trap depths and a two-layer array of atom nanotraps, which should have important applications in the manipulation of cold atoms and collective resonance fluorescence.