Collective excitations of magnetoplasma in semi-infinite n-i-p-i superlattices

A theoretical investigation has been made of the collective (bulk and surface) excitations in a semi-infinite n-i-p-i superlattice system in the presence of a magnetic field oriented perpendicular to the interfaces and to the direction of propagation. The thicknesses of the constituent layers is assumed to be sufficiently large so that the quantum-well effects can be ignored. The material layers are characterized by frequency- and magnetic-field-dependent dielectric functions. The magnetoplasma modes are defined by electromagnetic fields that are localized at and decay exponentially away from the interfaces and from the end of the superstructure. The general dispersion relations are derived using a fully retarded theory in the framework of a transfer-matrix method. Numerical examples are presented for several illustrative cases.