Temporally multiplexed storage of images in a Gradient Echo Memory
  We study the storage and retrieval of images in a hot atomic vapor using the gradient echo memory protocol. We demonstrate that this technique allows for the storage of multiple spatial modes. We study both spatial and temporal multiplexing by storing a sequence of two different images in the atomic vapor. The effect of atomic diffusion on the spatial resolution is discussed and characterized experimentally. For short storage time a normalized cross-correlation between a retrieved image and its input of 88 % is reported. 
Quentin Glorieux, Jeremy B. Clark, Alberto M. Marino, Zhifan Zhou, and   Paul D. Lett
quant-ph physics.atom-ph