Geometric resonances in the magnetoresistance of hexagonal lateral superlattices
arXiv:1208.4480 · doi:10.1103/PhysRevB.86.235315
Abstract
We have measured magnetoresistance of hexagonal lateral superlattices. We observe three types of oscillations engendered by periodic potential modulation having hexagonal-lattice symmetry: amplitude modulation of the Shubnikov-de Haas oscillations, commensurability oscillations, and the geometric resonances of open orbits generated by Bragg reflections. The latter two reveal the presence of two characteristic periodicities, sqrt{3} a / 2 and a / 2, inherent in a hexagonal lattice with the lattice constant a. The formation of the hexagonal-superlattice minibands manifested by the observation of open orbits marks the first step toward realizing massless Dirac fermions in semiconductor 2DEGs.
11 pages, 9 figures, minor revision
References in corpus (6)
- Engineering artificial graphene in a two-dimensional electron gas
- Making Massless Dirac Fermions from Patterned Two-Dimensional Electron Gases
- Delocalized-localized transition in a semiconductor two-dimensional honeycomb lattice
- Modulation of the Shubnikov-de Haas Oscillation in Unidirectional Lateral Superlattices
- Fourier analyses of commensurability oscillations in Fibonacci lateral superlattices
- Higher order terms in the geometric resonance of open orbits in unidirectional lateral superlattices