Single-photon transistor based on cavity electromagnetically induced transparency with Rydberg atomic ensemble

A scheme is presented to realize a single-photon transistor based on cavity quantum electrodynamics (QED) with Rydberg atomic ensemble. By combining the advantages of the cavity-enhanced interaction and Rydberg blockade, we achieve a high gain single-photon transistor. The numerical calculation shows that by using one single gate photon more than one thousand source photons can be switched.