ELFT HÍRADÓ

[Szeminárium koordinátor <szfi-seminar AT wigner.mta.hu>]

SZFI SzemináriumTajkov ZoltánELTE (vendéglátó: Juhász Róbert)Competition of 
trivial and topological phases in graphene based hybrid systems2020. február 
11. kedd, 10.00, KFKI Telephely, I. épület 1. emeleti TanácsteremTuning 
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 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 
szívesen látunk! - Everyone is welcome to attend.Juhász 
Róbertszfi-seminar AT wigner.mta.hu