Low-Frequency Surface Plasmons in Multicoaxial Negative-Index Metamaterial Cables

We employ an elegant response function theory, which does not require matching of the messy boundary conditions,
to investigate the surface plasmon excitations in the multicoaxial cylindrical cables made up of
negative-index metamaterials. The multicoaxial cables with dispersive metamaterial components exhibit a
rather richer (and complex) plasmon spectrum with each interface supporting two modes: one TM and the
other TE for m ≠ 0 (the integer order of the Bessel function). The cables with nondispersive metamaterial components
bear a different tale: they do not support simultaneously both TM and TE modes over the whole range
of propagation vector. The computed local and total density of states enable us to substantiate spatial positions
of the modes in the spectrum. Such quasi-one-dimensional systems as studied here should prove to be the milestones
of the emerging optoelectronics and telecommunications systems. [See, e.g., M.S. Kushwaha and B. Djafari-Rouhani,
J. Opt. Soc. Am. B 27, 148 (2010); B 27, 605 (2010); Mod. Phys. Lett. B 27, 1330013 (2013).]