A study of the magnetoplasmons of a cylindrical quasi-one-dimensional electron system is given in the presence of an axial magnetic field B. A two-subband system is considered and the dispersion relations for both intrasubband and intersubband magnetoplasmons are obtained using the exact infinite wall eigenfunctions. It is demonstrated that the application of a longitudinal B changes the mode frequencies for both types of excitations. The model includes both local-field corrections, which are shown to be important, and the Hartree potential, which is given in closed form.

• Received 15 July 1993

DOI:https://doi.org/10.1103/PhysRevB.48.18280