Imperial College London
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ProfessorJohannesLischner

Faculty of Engineering, Department of Materials

Professor of Theory and Simulation of Materials
 
 
 
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Contact

 

+44 (0)20 7594 9949j.lischner

 
 
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Location

 

342Bessemer BuildingSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Santos:2018:10.1103/PhysRevB.98.081407,
author = {Santos, FJD and Bahamon, DA and Muniz, RB and McKenna, K and Castro, EV and Lischner, J and Ferreira, A},
doi = {10.1103/PhysRevB.98.081407},
journal = {Physical Review B},
title = {Impact of complex adatom-induced interactions on quantum spin Hall phases},
url = {http://dx.doi.org/10.1103/PhysRevB.98.081407},
volume = {98},
year = {2018}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - © 2018 American Physical Society. Adsorbate engineering offers a seemingly simple approach to tailor spin-orbit interactions in atomically thin materials and thus to unlock the much sought-after topological insulating phases in two dimensions. However, the observation of an Anderson topological transition induced by heavy adatoms has proved extremely challenging despite substantial experimental efforts. Here, we present a multiscale approach combining advanced first-principles methods and accurate single-electron descriptions of adatom-host interactions using graphene as a prototypical system. Our study reveals a surprisingly complex structure in the interactions mediated by random adatoms, including hitherto neglected hopping processes leading to strong valley mixing. We argue that the unexpected intervalley scattering strongly impacts the ground state at low adatom coverage, which would provide a compelling explanation for the absence of a topological gap in recent experimental reports on graphene. Our conjecture is confirmed by real-space Chern number calculations and large-scale quantum transport simulations in disordered samples. This resolves an important controversy and suggests that a detectable topological gap can be achieved by increasing the spatial range of the induced spin-orbit interactions on graphene, e.g., using nanoparticles.
AU  - Santos,FJD
AU  - Bahamon,DA
AU  - Muniz,RB
AU  - McKenna,K
AU  - Castro,EV
AU  - Lischner,J
AU  - Ferreira,A
DO  - 10.1103/PhysRevB.98.081407
PY  - 2018///
SN  - 2469-9950
TI  - Impact of complex adatom-induced interactions on quantum spin Hall phases
T2  - Physical Review B
UR  - http://dx.doi.org/10.1103/PhysRevB.98.081407
VL  - 98
ER  -
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