Optical Storage with Electromagnetically Induced Transparency in a Dense Cold Atomic Ensemble

We experimentally investigate optical storage with electromagnetically induced transparency in a dense cold 85Rb atomic ensemble. By varying the optical depth (OD) from 0 to 140, we observe that the optimal storage efficiency has a saturation value of 50% as OD > 50. Our result is consistent with that obtained from hot vapor cell experiments. © 2011 Optical Society of America