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Quantum oscillations in a lead chalcogenide three- dimensional Dirac system

The de Haas–van Alphen (dHvA) and the Shubnikov–de Haas (SdH) oscillations were used to probe the properties of the Fermi surface in single crystals of Pb0.83Sn0.17Se with reduced charge concentration. Pronounced low-frequency oscillations of ∼8 T in the [001] direction were observed, confirming the single Fermi surface cross section. Due to the low effective charge concentration, the ultraquantum limit is reached already at ∼10 T. We observe π-Berry phase shift in the phase of both dHvA and SdH oscillations, which confirms the 3D Dirac nature of the energy band dispersion. In the construction of the Landau level diagram we use a combined indexing method for conductivity, magnetic susceptibility, and magnetization, which is based on the indexing used in the topological insulators. Moreover, the reliability of the indexing method is increased because we use, beside minima and maxima, zeros of the oscillations as well. Different microscopic parameters were calculated from the quantum oscillations in the magnetization, conductivity, and resistivity.

Quantum oscillations ; Dirac system ; Correlated topological phases ; Strong spin orbit

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