Magnetoresistance and robust resistivity plateau in MoAs2
  We have grown the MoAs$_2$ single crystal which crystallizes in a monoclinic structure with C2/m space group. Transport measurements show that MoAs$_2$ displays a metallic behavior at zero field and undergoes a metal-to-semiconductor crossover at low temperatures when the applied magnetic field is over 5 T. A robust resistivity plateau appears below 18 K and persists for the field up to 9 T. A large positive magnetoresistance (MR), reaching about 2600\% at 2 K and 9 T, is observed when the field is perpendicular to the current.The MR becomes negative below 40 K when the field is rotated to be parallel to the current. The Hall resistivity shows the non-linear field-dependence below 70 K. The analysis using two-band model indicates a compensated electron-hole carrier density at low temperatures. A combination of the breakdown of Kohler's rule, the abnormal drop and the cross point in Hall data implies that a possible Lifshitz transition has occurred between 30 K and 60 K, likely driving the compensated electron-hole density, the large MR as well as the metal-semiconductor transition in MoAs$_2$. Our results indicate that the family of centrosymmetric transition-metal dipnictides has rich transport behavior which can in general exhibit variable metallic and topological features. 
Jialu Wang, Lin Li, Wei You, Tingting Wang, Chao Cao, Jianhui Dai,   Yuke Li
cond-mat.mtrl-sci