Weak-light gap solitons in a resonant three-level system

We propose a scheme of generating optical gap solitons in a resonant three-level atomic system via electromagnetically induced transparency. We demonstrate, both analytically and numerically, that by means of a strong standing-wave control field the soliton with oscillating frequency within the band gap of a weak probe field can appear. Different from conventional passive optical media, the gap soliton in such highly resonant system can be created with very weak light intensity and can be manipulated in a controllable way.