Figure 1: Magnetic torque and resistivity of NbAs across the quantum limit.
From: Magnetic torque anomaly in the quantum limit of Weyl semimetals
These data were measured at a temperature of 4 K and at an angle of 25° off the c-axis towards the a-axis. (a) The low-field torque follows the conventional quadratic behaviour and shows strong quantum oscillations up to the quantum limit (orange line). Above the quantum limit, the torque grows strongly in magnitude, signalling the loss of the Berry-paramagnetic component beyond the quantum limit. In contrast to the torque, there is no change in behaviour in the smoothly saturating magnetoresistance beyond the last quantum oscillation. The torque was measured in pulsed fields up to 65 T, and resistivity in dc-fields up to 45 T. The quantum limit field is self-consistently determined as the position of the last quantum oscillations (b) and via the de Haas-van Alphen frequency (c) indicating the two close-by extremal orbits F1 and F2.
