Measuring atomic dimensions by transmission of Rydberg atoms through micrometre size slits

The authors have measured the transmission of a beam of Rydberg atoms through a metallic grating made of an array of micrometre size slits. The transmission decreases linearly with the square of the principal quantum number n, with a cut-off for a maximum n value. These results are in qualitative agreement with a simple theory of atom-metal electron exchange based on an electrostatic image model. This experiment provides an unusual comparison between the dimensions of atoms and the size of a 'classical' manufactured object.