Author: Valued eMachines Customer
Last saved by: Евгений
Company: eMachines

Specialization: 010700/03 Physics of Condensed Matter
Curriculum: 24 Nanoelectronics
Program manager :prof. Dr. А.S. Shulakov
Department of solid state electronics
Supervisor: Prof. Dr. G.G. Vladimirov, Prof. Dr. A.M. Shikin
Referee: Prof. Dr. A.P. Baraban

Spin-orbit splitting of π - states of graphene in case of combined intercalation of Bi and precious metals
E. V. Zhizhin

The quantity of the spin-orbit splitting of the electronic states of graphene is negligible, but the intercalation of Au atoms under the graphene monolayer on the Ni (111) surface leads to a significant spin-orbit splitting of the π-states of graphene. On the other hand, the intercalation of Cu atoms under the graphene monolayer on the Ni (111) surface does not lead to the spin-orbit splitting of the π-states of graphene. It was assumed that the effects observed during the intercalation of Au atoms under the graphene monolayer on the Ni (111) surface are largely conditioned by the hybridization of the π-states of graphene with the 5d-states of Au, as well as high intra-atomic potential of the gradient characteristic of the atoms of Au as a heavy metal.
In this research the methods of photoelectron spectroscopy with angular and spin resolution were used to investigate the  electronic and spin structure of the graphene monolayer on the Ni (111) surface after the intercalation of Bi atoms and joint intercalation of Bi and Cu, as well as Bi and Au. The choice of Bi as an intercalation metal is conditioned by a fundamentally different electronic structure of the valence band in contrast to the precious metal atoms. There are no valent d-electrons. Besides Bi (the atomic number Z = 83) is a heavy metal like Au (Z = 79).
The photoelectron spectra for these systems have been obtained. It is shown that the intercalation of Bi atoms, as well as joint intercalation of Bi and Au, or Cu and Bi under the graphene monolayer on the Ni (111) surface leads to a partial blocking of the interaction of graphene with a Ni(111) substrate. After the intercalation of the corresponding elements the electronic structure of graphene is close to the electronic structure characteristic of quasi-free graphene with a gap near the Fermi level. It should be noted that in the case of joint intercalation of Bi and Cu there are no gaps of the dispersion dependence caused by the «avoid-crossing» effect in contrast to the intercalation of Au, Cu, Bi and Au.
It is established that only the existence of the high intra-potential gradient, typical of Bi atoms, is not a sufficient condition for the substrate-induced spin-orbit splitting of the π-states of graphene. The joint intercalation of Bi and Au leads to the induced spin-orbit splitting of the π-states of ~ 20-30meV. In the case of joint intercalation of Bi and Cu the spin-orbit splitting of the π-states of graphene cannot be found.
The list of the publications
1. Е.V.Zhizhin, A.A. Popova,  D.Е. Marchenko,  A.G. Rybkin, , I.I. Klimovskikh,  G.G. Vladimirov, A.M. Shikin «The modification of the induced spin-orbit splitting of π - states of graphene in case of the combined intercalation of Bi and precious metals» // was submitted in Bulletin of the Russian Academy of Sciences. Physics, 2012.
2. Е.V.Zhizhin, A.A. Popova,  D.Е. Marchenko,  A.G. Rybkin, , I.I. Klimovskikh,  G.G. Vladimirov, A.M. Shikin  «The modification of the nduced spin-orbit splitting of π - states of graphene in case of the combined intercalation of Bi and precious metals». The Book of theses of XVI International Symposium «Nanophysics & Nanoelectronics», Nizhny Novgorod, Russia, 2012.
3. A.M. Shikin, A.A. Popova, Е.V.Zhizhin, D.Е. Marchenko, A.Varykhalov, O. Rader                «Graphene and spintronic. The effects of modulating induced by spin-orbit splitting». The Book of thesis of XVI International Symposium «Nanophysics & Nanoelectronics», Nizhny Novgorod, Russia, 2012.
4. Е.V.Zhizhin «The adsorption of carbon atoms on the surface of silicon oxide».The Book of Abstracts of the  International Student Conference «Science and Progress», St. Petersburg State University, 2010.
5. Е.V.Zhizhin  «The adsorption of carbon atoms on the surface of silicon oxide» Book of theses, International Student Conference «Science and Progress», St. Petersburg State University, 2010.
6. Е.V.Zhizhin «The modification of the induced spin-orbit splitting of π - states of graphene in case of the combined intercalation of Bi and precious metals”. The Book of Abstracts of the International Student Conference «Science and Progress», St. Petersburg State University, 2011.
7. Е.V.Zhizhin «The modification of the induced spin-orbit splitting of π - states of graphene in case of the combined intercalation of Bi and precious metals». The Book of theses of the International Student Conference «Science and Progress», St. Petersburg State University, 2011.
8. E.V. Zhizhin, A.A. Popova, A.G. Rybkin, G.G. Vladimirov, A.M. Shikin «The modification of the induced spin-orbit splitting of π - states of graphene under joint intercalation of Bi and Au». The Book of Abstracts of the German-Russian Conference on «Fundamentals and Applications of Nanoscience», Free University of Berlin, 2012.