The quantum anomalous Hall effect (QAHE) is a remarkable phenomenon observed in certain topological insulators, where a quantized Hall conductance is present even in the absence of an external magnetic field. This effect arises due to the topological nature of the material, where the electronic wave functions form topologically protected edge states with non-zero Chern number. These edge states exhibit chiral transport, allowing charge carriers to flow in one direction only, with high efficiency and without dissipation. The QAHE has significant implications for spintronics, quantum computing, and other applications requiring low-energy, robust transport channels.
