Resolve the magnetic field-induced Lifshitz transition and quantum oscillations in Kondo insulators YbB₁₂

There have been recent great interests in the observation of magnetic quantum oscillations in the insulating phase of the Kondo system YbB₁₂. Our previous work indicated clear quantum oscillations in torque and transport measurements[1]. At two characteristic magnetic fields (μ₀H =19.6 T and μ₀H = 31 T), signatures appear in the Hall coefficient, magnetic torque, and magnetoresistance; the latter characteristic field coincides with the occurrence of a change in quantum-oscillation frequency.



I will present our attempts to resolve the possible field-induced Lifshitz transition at (μ₀H =19.6 T and μ₀H = 31 T) and quantum oscillations via heat capacity and thermoelectric measurements in high magnetic field up to 41T, which supports a novel two-fluid scenario in YbB12.

[1] Xiang, Z.; Chen, K.-W.; Chen, L.; Asaba, T.; Sato, Y.; Zhang, N.; Zhang, D.; Kasahara, Y.; Iga, F.; Coniglio, W.A.; Matsuda, Y.; Singleton, J.; Li, L., Hall Anomaly, Quantum Oscillations and Possible Lifshitz Transitions in Kondo Insulator YbB12 : Evidence for Unconventional Charge Transport, Phys. Rev. X 12, 021050 (2022)