Guiding light by the modulated electromagnetically induced transparency

We propose a scheme for guiding light by the modulated electromagnetically induced transparency (EIT) in a three-level atomic system. By using a periodically modulated control field, the linear and nonlinear susceptibilities are changed cyclically for the probe field, which results in the deflection of propagation direction of the probe beam. Propagation direction/path and output position of the probe soliton in the modulated EIT medium can be controlled precisely via adjusting the modulation period of the control field. By changing its initial amplitude, the probe beam can also be guided to a desired output position in the atomic system, driven by a periodic control field. These properties offer a novel way of soliton control, based on the modulated EIT effect.