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Video abstract for the article 'Raman superradiance and spin lattice of ultracold atoms in optical cavities' by S Safaei, Ö E Müstecaplıoğlu and B Tanatar (S Safaei et al 2013 New J. Phys. 15 083037). Read the full article in New Journal http://iopscience.iop.org/1367-2630/15/8/083037/. GENERAL SCIENTIFIC SUMMARY Introduction and background. The Dicke superradiant quantum phase transition with a Bose--Einstein condensate (BEC) in an optical cavity was observed in 2010 by a research team led by Tilman Esslinger at ETH Zurich. Simultaneously with the abrupt scattering of an incident laser off the BEC into the cavity at the threshold of the Dicke transition, superfluid BEC is observed to self-organize into a lattice as a supersolid. It is expected that novel quantum phases may emerge based upon this observation. We propose synthesis of a magnetic supersolid. Main results. We consider a BEC of atoms with two hyperfine states, which are coupled by a pump laser and the cavity field through a far-detuned excited state in a Raman scheme, inside a one-dimensional optical cavity. We numerically simulate the system to demonstrate that the cavity field undergoes Raman superradiance and the BEC self-organizes into robust ferromagnetic or ferrimagnetic spin lattices after a threshold of the pump intensity (see the figure). Wider implications. A large number of spins per lattice site makes the system advantageous for exploring magnetic supersolid properties. Coupling to the common cavity field would make spins at different lattice sites strongly correlated. Beyond mean-field, extension of our model can be used to explore such correlations. Our model brings optical lattices and spin lattices together in a compact and controllable cavity-QED environment providing a possible platform for quantum information applications, as well as monitoring phase transitions and spin correlations with a Raman scheme.