A new and efficient proposal for all-optical tunable devices and systems using electromagnetically induced transparency (EIT) is proposed. For this purpose a slab doped with quantum dots for realization of three-level atomic system is considered. Density matrix formulation for evaluation of the proposed structure is used. The reflection and transmission coefficients of the considered slab are calculated and the related amplitude and phase quantities studied versus parameters of the structure. We show that some nanometer tuning with application of the control field is obtained. So, the proposed idea can open a new realization method of all-optical tunable devices and systems towards all-optical systems. † The second author is also with School of Engineering Emerging Technologies, University of Tabriz, Tabriz, Iran