ELFT HÍRADÓ

[Janos Asboth <asboth.janos AT wigner.mta.hu>]

Meghívó

BME Elméleti Fizika Szeminárium,

november 22. péntek 10h15,

1111 Budapest, Budafoki út 8., BME F III. magasföldszint 01.,
Elméleti Fizika Tanszék szemináriumi szoba

Tajkov Zotán (ELTE TTK, Fizikai Intézet):

Competition of trivial and topological phases in graphene based hybrid
systems

Tuning spin-orbit interaction in graphene samples promises several
revolutionary applications. One of the most striking effects is the
appearance of a quantum spin Hall phase as proposed by Kane and Mele. Since
the intrinsic spin-orbit coupling is weak in graphene one needs to turn to
alternative methods in order to reach the topological phase. Combining
graphene with other novel layered materials is a possible way for
engineering the band structure of charge carriers. Strong spin-orbit
coupling in BiTeX compounds and the recent fabrication of a single layer of
BiTeI points towards a feasible experimental realization of a Kane-Mele
phase in graphene-based heterostructures. In our previous work, we explored
the electronic structure and topological phase diagram of hybrid systems
built from graphene and BiTeX (X=I, Br, Cl) layers. We showed that
structural stress inherently present in fabricated samples could easily
induce a topological phase transition thus turning the sample in a novel
experimental realization of a time reversal invariant topological
insulator. During the talk I would like to show a model that captures the
essence of the undergoing physical processes in these systems focusing on
the low-energy degrees of freedom of the perturbed graphene lattice.

Minden érdeklődőt szeretettel várunk.

Asbóth János
szemináriumi koordinátor