Atomic nanofabrication by laser manipulation of a neutral cesium beam

In this work, we report on the results of a nanolithography experiment with a cold cesium beam. We have realized a brilliant and collimated cesium beam with a low longitudinal velocity (10 m/s) exploiting laser cooling techniques, in particular a pyramidal atomic funnel. The cesium atomic beam has been utilized to pattern gold substrates, using Self Assembled Monolayers (SAM) of thiols as resist, and a wet etching process. The pattern generated by a light mask, a one-dimensional standing e.m. wave, was characterized by diffraction and Atomic Force Microscopy (AFM) measurements, showing the presence of lines spaced half the wavelength of the standing wave (426 nm) with lateral size well below 100 nm.