Modification of induced spin-orbit splitting of the π states of graphene during the joint intercalation of Bi and noble metals

Spin splitting of Dirac fermions in graphene on Ni intercalated with alloy of Bi and Au

“…These modifications of spin structure of graphene were described in framework of the spindependent avoid-crossing effects between the p states of graphene and essentially spin-orbit split 5d states of Au and Ir. [7,[11][12][13][14]. In accordance with this, branches of graphene p states with different orientation of spin only interact with those subbands of 5d metal which have same spin orientations.…”

“…Cu) under the graphene on Ni(1 1 1) is also accompanied by a hybridization between p states of graphene and 3d states of Cu, it is not causing any detectable spin-orbit splitting of the Dirac cone in graphene [7,11,12]. We have earlier established that the effect of induced spin-orbit splitting of p states in graphene is driven by two factors -firstly, electronic hybridization between p states of graphene and the d states of metal, and, secondly, high atomic number of contacting metal, which guarantees strong spin-orbit interactions as well as significant inner-atomic potential gradient [7,11].…”

“…These materials are 79 Au and 83 Bi. The latest, on contrast to Au, has no d electronic states in the valence band, which are known to induce extrinsic spin-orbit splitting in graphene [7,11] through spin-dependent (d-p) interfacial hybridization between graphene and the intercalated layer. In particular, we investigate the intercalation of graphene/Ni(1 1 1) with pure Au, pure Bi and with a mixture of them, and show that a variation of mutual concentrations of Bi and Au in intercalated interlayer allows for tuning of spin-orbit splitting and the band gap in the Dirac cone.…”

“…between them and on peculiarities of electronic structure of the substrate. Depending on the situation one can observe charge doping of graphene, formation of an energy gap between the Dirac cones of the p and p à states, appearance of local band gaps in the dispersions of p states as a result of avoid-crossing effects in the interaction of graphene and substrate bands [6][7][8][9][10][11][12][13]. Possibilities to modify the spin structure of graphene through its interaction with high spin-orbit metals (Au, Ir, Pt) and spin-dependent avoid crossing effects [6] have been recently demonstrated experimentally [10,11,[13][14][15].…”

Growth of graphene monolayer by “internal solid-state carbon source”: Electronic structure, morphology and Au intercalation

“…The most popular methods used now are the methods of mechanical exfoliation from a graphite monocrystal [1][2][3], catalytic reaction of cracking of carbonaceous gases on the surface of monocrystals and monocrystalline films of transition metals [8][9][10][11][12][13][14][15], and the method of thermal carbidization of silicon carbide (SiC) monocrystals [16,17]. At the present moment the method of cracking of carbon-contained gases (like propylene (C 3 H 6 )) on the surface of Ni(111) monocrystalline film is widely spread due to its simplicity and a very small mismatch between graphene and Ni(111) lattice parameters.…”