ELFT HÍRADÓ

[Andras Palyi <andraspalyi AT caesar.elte.hu>]

Az ELTE Nanofizika Szeminarium jovo hetfoi eloadasa:


Asboth Janos (Wigner FK SzFI): Chiral symmetry and end states in periodically 
driven 1D systems

Idopont: 2014. szeptember 15., hetfo, 10:15
Helyszin: ELTE Eszaki Tomb, 5.128-as terem (1117 Budapest, Pazmany Peter 
setany 1/A)

Kivonat:
"Topological band insulators are noninteracting lattice systems that host 
protected excitations at their boundaries, whose number is predicted by 
topological invariants of the bulk Hamiltonian. A quasi-one-dimensional 
system, i.e., a wire, can only be topological insulator in the presence of 
particle-hole symmetry or chiral symmetry. The simplest model for such a 
system is the Su-Schrieffer-Heeger model for polyacetylene. In this talk I 
will show how the theory of chiral symmetric one-dimensional topological 
insulators can be generalized to periodically driven quantum wires. In these 
systems, the bulk topological invariants cannot be derived from the effective 
Hamiltonian: more detailed information about how the timestep is performed is 
required. As a concrete example, I illustrate our results on the periodically 
driven Su-Schrieffer-Heeger (SSH) model, where we give a direct visual 
interpretation of the novel topological invariants. If the hopping amplitudes 
are real, the end states here are Floquet Majorana fermions.

Asboth, Tarasinski, Delplace, arXiv:1405.1709"


Tovabbi program: http://wigner.elte.hu/science/?q=seminar

Minden erdeklodot szivesen latunk.

Udvozlettel,
Palyi Andras