Extended Data Fig. 9: Hall resistance behaviors under different measuring conditions.
From: Orbital multiferroicity in pentalayer rhombohedral graphene
a & b, 2D color maps of Rxy in the droplet region corresponding to forward and backward scanning of E with a small negative magnetic field B = −20 mT. c & d, The same plot as in a and b but with scanning density ne at B = 20 mT. e & f, The same plot as in a and b but with scanning density ne with B = −20 mT. Rxy changes the sign as we scan E but stays the same sign as we scan ne. This is due to the fact that the magnetic moment for a given valley will reverse as we scan E but not ne. As we scan n, the system will choose to polarize to the valley with the magnetic moment parallel with external B. The random jumps near E = 0 when scanning ne is because the magnetic moment near E = 0 is very small and the coupling to the external B field is weak, so the system cannot decide which valley to choose.
