Our paper on quantum memory collapses and revivals was published in Physical Review A!
In the paper, we show our experimental observation of dark-state polariton collapses and revivals in a quantum memory based on electromagnetically induced transparency on a cloud of cold cesium atoms in a magnetic field. We suppress the dark-state polariton collapses by polarizing the atoms towards one of the stretched Zeeman states and optimizing the frequency detuning of the control beam. In this way, we demonstrate a quantum memory with only partial dark-state polariton collapses, making the memory usable at any storage time, not only at discretized times of revivals. We obtain storage time of more than 400 μs, which is ten times longer than what we can achieve by trying to annul the magnetic field.