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【Abstract】

Magnetic quantum oscillations play a key role in resolving the Fermi surfaces and electronic structures and confirming the prediction of topological materials. Studying quantum oscillations is also essential for the broad field of correlated quantum materials. I will discuss the Chern Fermi pocket of the recently discovered Kagome metal CsV3Sb5. Thanks to the extremely high magnetic field, we found the magnetic breakdown between the Chern orbits and the conventional orbits. From the “spin-zero” effect, the Lande’ g factor is found to be as large as 14. The Berry curvature of the Chern Fermi pocket needs to be involved in generating large orbital moments.
In a similar contest, Kondo insulator YbB12 revealed quantum oscillations even in the insulating state. By employing methods like torque magnetometry, electrical resistivity, and AC conductivity in YbB12, we were able to trace the pattern of these quantum oscillations across both the low-field insulating state and the high-field induced metallic state.