Comment on “Magnetotransport signatures of a single nodal electron pocket constructed from Fermi arcs”

We comment on the recent work [N. Harrison et al., Phys. Rev. B 92, 224505 (2015)] which attempts to explain the sign reversal and quantum oscillations of the Hall coefficient observed in cuprates from a single-nodal diamond-shaped electron pocket with concave arc segments. Given the importance of this work, it calls for closer scrutiny. Their conclusion of sign reversal of the Hall coefficient depends on a nongeneric rounding of the sharp vertices. Moreover, their demonstration of quantum oscillation in the Hall coefficient from a single pocket is unconvincing. We maintain that at least two pockets with different scattering rates is necessary to explain the observed quantum oscillations of the Hall coefficient.

Figure 1

Schematic diamond-shaped electron pocket Fermi surface [1]. This pocket is supposed to be centered around the nodal point $(k_x,k_y)=(\frac{\pi }{2},\frac{\pi }{2})$ in the Brillouion zone. The lattice spacing is set to unity. When viewed as a part of a circle, each arc has a subtending angle $\alpha$ to the origin of that circle.