Magnetic field dependence of vibrational excitations in a two-dimensional triangular Wigner crystal

It is shown that a static magnetic field applied perpendicular to a quasi twodimensional Wigner crystal lifts the degeneracy, e.g., of transverse and longitudinal vibrational frequencies and modifies their dispersion. The dependence of the effect on the magnitude of the applied field, on the electron surface concentration, and its relevance for observing a two-dimensional Wigner crystal are investigated quantitatively for a triangular lattice of a three-layer structure in harmonic approximation.