Giant nonlinearities via simultaneous electromagnetically- and self-induced transparencies in doped photonic crystals

This paper studies a strong modulation of the phase of a weak pulse subject to electromagnetically-induced transparency (EIT) by a control pulse in the form of an self-induced transparency (SIT) gap soliton (GS) moving at the same slow velocity. The aim of this work is to match the group velocities of the weak probe field subject to EIT and the free-propagating field having the form of a slow SIT GS.