Observation of giant non-reciprocal charge transport from quantum Hall states in a topological insulator.

Symmetry breaking in quantum materials is of great importance and can lead to non-reciprocal charge transport. Topological insulators provide a unique platform to study non-reciprocal charge transport due to their surface states, especially quantum Hall states under an external magnetic field. Here we report the observation of non-reciprocal charge transport mediated by quantum Hall states in devices composed of the intrinsic topological insulator Sn-Bi 1.1 Sb 0.9 Te 2 S, which is attributed to asymmetric scattering between quantum Hall states and Dirac surface states. A giant non-reciprocal coefficient of up to 2.26 × 10 5  A -1 is found. Our work not only reveals the properties of non-reciprocal charge transport of quantum Hall states in topological insulators but also paves the way for future electronic devices.