Low-Density Ferromagnetism in Biased Bilayer Graphene
Castro, Eduardo V.
; Peres, N. M. R.
; Stauber, T.
;
Silva, N. A.
Physical Review Letters Vol. 100, Nº 18, pp. 186803-1 - 186803-4, May, 2008.
ISSN (print): 0031-9007
ISSN (online): 1079-7114
Scimago Journal Ranking: 6,19 (in 2008)
Digital Object Identifier: 10.1103/PhysRevLett.100.186803
Abstract
We compute the phase diagram of a biased graphene bilayer. The existence of a ferromagnetic phase is discussed with respect to both carrier density and temperature. We find that the ferromagnetic transition is first-order, lowering the value of U relatively to the usual Stoner criterion. We show that in the ferromagnetic phase the two planes have unequal magnetization and that the electronic density is holelike in one plane and electronlike in the other.
