Bipolarity Induced Gigantic Intrinsic Anomalous Hall Effect in Iterative‐Grown Kagome Semimetal Co3Sn2S2 Crystals

As a magnetic Weyl semimetal with broken time‐reversal symmetry, kagome‐lattice Co3Sn2S2 hosts a plethora of exotic quantum phenomena due to the interplay between magnetism, electronic correlations, and non‐trivial band topology. However, achieving high crystal quality, which is crucial for understanding intrinsic mechanisms and enhancing the physical properties, still remains a significant challenge. Here, the synthesis of ultra‐high‐quality Co3Sn2S2 single crystals is reported via an iterative chemical vapor transport (iterative‐CVT) approach, achieving gigantic anomalous Hall conductivity (AHC) of 1600 Ω−1cm−1, anomalous Hall angle (AHA) of 40%, and exceptional carrier mobility and magnetoresistance of 10 490 cm2 V−1 s−1 and 2500%. Intriguingly, a striking 65% enhancement of the AHC is observed upon increasing the temperature from 2 to 50 K, attributed to the presence of bipolar carrier contributions from the Weyl bands. Furthermore, an ultra‐narrow flat band near the Fermi level is directly visualized by angle‐resolved photoemission spectroscopy, suggesting enhanced electron correlations that render the electron concentration and hence AHC highly temperature‐dependent. The findings provide a robust material platform to inspire further research into emergent quantum phenomena in magnetic kagome systems.