Spin image of an atomic vapor cell with a resolution smaller than the diffusion crosstalk free distance

Abstract

The diffusion crosstalk free distance is an important parameter for spin images in atomic vapor cells and is also regarded as a limit on the spatial resolution. However, by modulating the pumping light both spatially and temporally using a digital micromirror device, a spin image of a vapor cell has been obtained with a distinguishable stripe width of 13.7~$\mu$m, which is much smaller than the corresponding diffusion crosstalk free distance of $\sim$138~$\mu$m. The fundamental limit on the spatial resolution as determined by diffusion and the uncertainty principle is analyzed.