Near-field scanner for moving molecules

We have fabricated using electron beam nanolithography a fixed slit near-he ld optical scanning device which uses near-field fluorimetry to achieve 200 nm spatial resolution of objects moving over the slits. We explore the bas ic physics of operating narrow slits in the waveguide cutoff mode and prese nt data from the passage of extended double-stranded DNA molecules passing over the slits as a first example of how this device can be used to do ultr ahigh spatial resolution mapping of long polymers.