Comparison of photonic crystal narrow filters with metamaterials and dielectric defects E. Lotfi, K. Jamshidi-Ghaleh, F. Moslem and H. Masalehdan Eur. Phys. J. D, 60 2 (2010) 369-372 Published online: 02 August 2010 DOI: 10.1140/epjd/e2010-00207-4