Effect of magnetic field on the coupling of 2D plasmons to nonlocal bulk plasmons

We report here on the effect of a magnetic field on the coupling of 2D plasmons to nonlocal bulk plasmons. The present analysis extends our recent field-free study of the spectrum of coupled collective modes arising from electronic excitations within the quantum well-bound state jointly with those within the continuum of states (but excluding any role of transitions from the bound state to the continuum). We employ a magnetic field generalization of the hydrodynamic model, which correctly represents the magnetic field dependence of the nonlocal principal bulk and 2D plasmons. Our results clearly show how, with increasing magnetic field, some of the modes belonging to the continuum of states split off and have negative dispersion in the long wavelength limit. These are new magnetoplasmons, not to be confused with Bernstein modes (which has been excluded from this analysis).