Time gap for temporal cloak based on spectral hole burning in atomic medium

We demonstrate the possibility of creating a time gap in the slow light based on spectral hole burning in a four-level Doppler broadened sodium atomic system. A time gap is also observed between the slow and the fast light in the hole burning region and near the burnt hole region, respectively. A cloaking time gap is attained in microseconds and no distortion is observed in the transmitted pulse. The width of the time gap is observed to vary with the inverse Doppler effect in this system. Our results may provide a way to create multiple time gaps for a temporal cloak.