We present the theoretical basis for a novel nano-optical trap for neutral atoms. The trap utilitzes plasmonic resonances of metallic nanoparticles to shape laser light fields in a subwavelength region. The combination of the laser field and auxilliary electrostatic fields provides a trapping potential for atoms. Blue-detuned from atomic resonance, the plasmon-enhanced laser field strongly damps atomic motion.

A new method to efficiently calculate electric fields surrounding nanospheres is used to study the interaction between light and metallic nanostructures. Theory and calculations for the modification of atomic properties such as excited state decay rates and energy levels due to the proximity of the nanostructure are presented. The interaction between atoms and light fields, including optical force, damping, and momentum diffusion are studied in detail. These interactions are synthesized to design an atomic nanotrap, whose properties including trapping potential, lifetime, and loading rates are further analyzed.