Single Airborne Dust Particles using Plasmonic Metal Films with Hole Arrays.

An airborne dust particle is trapped in the hole of a plasmonic metal film with a patterned array of holes (mesh) by pumping air through the mesh. Both scatter-free infrared spectra and scanning electron images are obtained on the same individual airborne dust particle, showing the feasibility of multiple, nondestructive experiments on a single, subwavelength particle. Ultimately, this may help to elucidate the effect of shape, orientation, and crystallinity on IR dust particle spectra.