Propagation of Broad Spectrum Pulse in EIT Medium

We investigate the possibility of broad spectrum pulse propagation in an electromagnetically induced transparency (EIT) medium without large distortion. The pulse is separated into different spectrum bands. Each band propagates in an EIT window whose center is adjusted to the band center. After proper phase compensations these bands are recombined. The outcoming pulse suffers little distortion and absorption, compared to the propagation in one EIT window. Using this method we can remove the restriction to pulse width in slow light experiments.