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that a truncated crystalline lattice could support special types of electronic states that are bound at the very edge of the semi-infinite periodic potential.1 These states, known in many fields as Tamm states, represent a special class of spa-tially localized surface waves, which, in general, may appear at interfaces between different physical media. An optical analog of linear Tamm states has been described theoretically and demonstrated experimentally for an interface separat-ing periodic and homogeneous dielectric materials.2 Despite the fact that many theoretical concepts have been success