Title:	Enhancing spin-orbit coupling of graphene using first-principles calculations
DNr:	SNIC 2019/7-18
Project Type:	SNIC Small Compute
Principal Investigator:	Shahid Sattar <shahid.sattar@lnu.se>
Affiliation:	Luleå tekniska universitet
Duration:	2019-03-14 – 2020-04-01
Classification:	10304
Keywords:

Abstract

While graphene offers countless exciting opportunities in nanoscale device fabrication, it is still challenging to harness its spin degree of freedom due to the weak spin-orbit coupling (SOC) strength. Numerous routes therefore have been proposed to enhance the SOC of graphene such as introducing defects [1], doping [2], hydrogenation and fluorination [3], decoration with adatoms [4], using metal clusters [5] and magnetic substrates [6]). On the other hand, van der Waals heterostructures of graphene with transition-metal dichalcogenides (TMDCs) also offer a viable approach to accomplish this task and to access hidden topological features of this ultrathin system. We therefore plan to employ density functional theory based first-principles calculations to study the electronic and spintronic properties of graphene in heterostructure with TMDCs. In particular, the focus will be to use proximity effects introduced by TMDCs to alter the SOC strength of graphene and explore its potential applications in spintronics devices. References: [1] M. V. Ulybyshev and M. I. Katsnelson, Magnetism and Interaction-Induced Gap Opening in Graphene with Vacancies or Hydrogen Adatoms: Quantum Monte Carlo Study, Phys. Rev. Lett. 114, 246801 (2015). [2] G. H. H\'ector, J. M. G. Rodr\'iguez, P. Mallet, M. Moaied, J. J. Palacios, C. Salagado, M. M. Ugeda, J. Y. Veuillen, F. Yndurain, and I. Brihuega, Atomic-Scale Control of Graphene Magnetism by Using Hydrogen Atoms, Science 352, 437-441 (2016). [3] J. Zhou, Q. Liang, and J. Dong, Enhanced Spin-Orbit Coupling in Hydrogenated and Fluorinated Graphene, Carbon 48, 1405 (2010). [4] C. Weeks, J. Hu, J. Alicea, M. Franz, and R. Wu, Engineering a Robust Quantum Spin Hall State in Graphene Via Adatom Deposition, Phys. Rev. X 1, 021001 (2011). [5] J. Balakrishnan, G. K. W. Koon, A. Avsar, Y. Ho, J. H. Lee, M. Jaiswal, S. J. Baeck, J. H. Ahn, A. Ferreira, M. A. Cazalilla, A. H. Castro Neto, and B. \"Ozyilmaz, Giant Spin Hall Effect in Graphene Grown by Chemical Vapour Deposition, Nat. Commun. 5, 4748 (2014). [6] J. B. S. Mendes, O. A. Santos, L. M. Meireles, R. G. Lacerda, L. H. V. Le\~ao, F. L. A. Machado, R. L. R. Suarez, A. Azevedo, and S. M. Rezende, Spin-Current to Charge-Current Conversion and Magnetoresistance in a Hybrid Structure of Graphene and Yttrium Iron Garnet, Phys. Rev. Lett. 115, 226601 (2015).