Topological transition of Dirac points in a microwave experiment.

Phys Rev Lett

Laboratoire Physique de la Matière Condensée, CNRS UMR 7336, Université Nice-Sophia Antipolis, Nice, France.

Published: January 2013

By means of a microwave tight-binding analogue experiment of a graphenelike lattice, we observe a topological transition between a phase with a pointlike band gap characteristic of massless Dirac fermions and a gapped phase. By applying a controlled anisotropy on the structure, we investigate the transition directly via density of states measurements. The wave function associated with each eigenvalue is mapped and reveals new states at the Dirac point, localized on the armchair edges. We find that with increasing anisotropy, these new states are more and more localized at the edges.

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http://dx.doi.org/10.1103/PhysRevLett.110.033902DOI Listing

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