Séminaire de groupe
|Massive chiral edge mode generation by classical harmonic deformations of the honeycomb zigzag nanoribbon|
|IVIC Caracas - Regensburg Universität|
|jeudi 12 décembre 2013 , 10h25|
|Salle de séminaire du groupe de Physique Statistique|
We present our results on the effects of harmonic deformations of the honeycomb lattice and show that they lead to generation of counter propagating edge states on the boundaries of a zigzag nanoribbon. The main salient feature of these additional edge states is that they correspond to chiral massive fermions with quadratic momentum dispersion, as opposed to the standard linear momentum contribution present in the static regime. By analyzing the low energy Dirac Hamiltonian we show that a topological phase transition occurs with these massive dressed fermionic states propagating along the boundaries with a sound velocity that is smaller than their typical (static) Fermi velocity. We argue that this new phase could experimentally be detected as slow edge modes with a sound velocity being determined from the measurement of the frequency difference between two resonant standing-wave modes in an acoustical interferometer.