Plasmon excitations in multicoaxial cables

We report on the theoretical investigation of plasmon excitations in multi-coaxial cables (MCC) within the framework of a Green-function theory in the absence of any applied magnetic field. As an application, we present illustrative examples on the dispersion characteristics of the confined and extended plasmons in the perfect as well as (geometrically) imperfect system. The computed local density of states (LDOS) enables us to specify the spatial positions of both kinds of modes existing in the system. The elegance of the formalism lies in the fact that it does not require the matching of the messy boundary conditions and in its simplicity and the compact form of the desired results. Such quasi-one dimensional systems are proving to be the backbone of the emerging optoelectronics and telecommunications systems.