We apply collective Raman scattering to create, store and retrieve spatiallymultimode light in warm rubidium-87 vapors. The light is created in aspontaneous Stokes scattering process. This is accompanied by the creation ofcounterpart collective excitations in the atomic ensemble -- the spin waves.After a certain storage time we coherently convert the spin waves into thelight in deterministic anti-Stokes scattering. The whole process can beregarded as a delayed four-wave mixing which produces pairs of correlated,delayed random images. Storage of higher order spatial modes up to microsecondsis possible owing to usage of a buffer gas. We study the performance of theRaman scattering, storage and retrieval of collective excitations focusing onspatial effects and the influence of decoherence caused by diffusion ofrubidium atoms in different buffer gases. We quantify the number of modescreated and retrieved by analyzing statistical correlations of intensityfluctuations between portions of the light scattered in the far field.
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