Quantum Anomalous Hall Effect (Theory)

Theoretical prediction (Liu, Qi, Dai, Fang & Zhang, 2008) that a magnetically-doped topological insulator (HgMnTe) could exhibit a quantized Hall conductance with zero external magnetic field -- unlike the ordinary quantum Hall effect (1980) or fractional QHE (1982), which both require a strong external field. Distinct phenomenon from generic "topological insulator" (already tracked); bare "quantum anomalous Hall effect" tested clean pre-2008 via OpenAlex noise test.