Spin g -factor due to electronic interactions in graphene

Abstract

The gyromagnetic factor is an important physical quantity relating the magnetic-dipole moment of a particle to its spin. The electron spin g-factor in vacuo is one of the best model-based theoretical predictions ever made, showing agreement with the measured value up to ten parts per trillion [J. Schwinger, Phys. Rev. 73, 416 (1948)PHRVAO0031-899X10.1103/PhysRev.73.416; R. S. Van Dyck, Jr., Phys. Rev. Lett. 59, 26 (1987)PRLTAO0031-900710.1103/PhysRevLett.59.26; D. Hanneke, Phys. Rev. Lett. 100, 120801 (2008)PRLTAO0031-900710.1103/PhysRevLett.100.120801; T. Aoyama, Phys. Rev. Lett. 109, 111807 (2012)PRLTAO0031-900710.1103/PhysRevLett.109.111807]. However, for electrons in a material the g-factor is modified with respect to its value in vacuo because of environment interactions. Here, we show how interaction effects lead to the spin g-factor correction in graphene by considering the full electromagnetic interaction in the framework of pseudo-QED [A. Kovner, Phys. Rev. B 42, 4748 (1990)PRBMDO0163-182910.1103/PhysRevB.42.4748; N. Dorey, Nucl. Phys. B 386, 614 (1992)NUPBBO0550-321310.1016/0550-3213(92)90632-L; S. Teber, Phys. Rev. D 86, 025005 (2012)PRVDAQ1550-799810.1103/PhysRevD.86.025005; S. Teber, Phys. Rev. D 89, 067702 (2014)PRVDAQ1550-799810.1103/PhysRevD.89.067702; E. C. Marino, Nucl. Phys. B 408, 551 (1993)NUPBBO0550-321310.1016/0550-3213(93)90379-4]. We compare our theoretical prediction with experiments performed on graphene deposited on SiO2 and SiC, and we find a very good agreement between them.