Nanoscale Resolution Fluorescence Using Cold Atoms

We suggest a new type of scanning fluorescence microscope that is capable of resolving nanometer size objects in the far field.~ The key idea is to use a position dependent Stark Shift of a Raman transition to produce atomic excitation tightly confined to nanometer spatial scales. We present numerical simulations that demonstrates a resolution that is 40 times smaller than the wavelength of light.~ We discuss in detail a possible first experiment where a nanoscale object is embedded in an ultracold atomic cloud and a high resolution image is obtained at the far field.~