Two-dimensional Dirac fermions in YbMnBi2 antiferromagnet
  We report two-dimensional quantum transport and Dirac fermions in YbMnBi2 single crystals. YbMnBi2 is a layered material with anisotropic conductivity and magnetic order below 290 K. Magnetotransport properties, nonzero Berry phase and small cyclotron mass indicate the presence of quasi two dimensional Dirac fermions. Quantum oscillations in Hall resistivity suggest the presence of both electron and hole parts of the Fermi surface whereas the Berry phase suggests spin-orbit coupling. 
Aifeng Wang, I. Zaliznyak, Weijun Ren, Lijun Wu, D. Graf, V. O.   Garlea, J. B. Warren, E. Bozin, Yimei Zhu and C. Petrovic
cond-mat.mes-hall cond-mat.mtrl-sci cond-mat.str-el