Surface-assisted ultralocalization in nondiffracting beams arXiv:1001.3204v1 [physics.optics] 19 Jan 2010 Juan J. Miret Departamento de ´ Optica, Universidad de Alicante, P.O. Box 99, Alicante, Spain. Carlos J. Zapata-Rodr´ıguez ∗ Departamento de ´ Optica, Universidad de Valencia, Dr. Moliner 50, 46100 Burjassot, Spain. (Dated: August 31, 2018) Abstract We present a family of localized radiation modes in multilayered periodic media, where in-phase superposition of p-polarized waves leads to radiative confinement around the beam axis. Excitation of surface plasmon polaritons yields an enhanced localization normally to the interfaces. On the other hand, the spectral filtering induced by the presence of bandgaps allows to achieve transverse superresolution on the interfaces. Subwavelength beamwidths along an infinitely long distance might potentially be obtained. PACS numbers: 42.25.Bs, 42.82.Et ∗ carlos.zapata@uv.es 1