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arXiv · 2212.12452

Unreliability of two-band model analysis of magnetoresistivities in unveiling temperature-driven Lifshitz transition

Abstract

Recently, anomalies in the temperature dependences of the carrier density and/or mobility derived from analysis of the magnetoresistivities using the conventional two-band model have been used to unveil intriguing temperature-induced Lifshitz transitions in various materials. For instance, two temperature-driven Lifshitz transitions were inferred to exist in the Dirac nodal-line semimetal ZrSiSe, based on two-band model analysis of the Hall magnetoconductivities where the second band exhibits a change in the carrier type from holes to electrons when the temperature decreases below T = 106 K and a dip is observed in the mobility versus temperature curve at T = 80 K. Here, we revisit the experiments and two-band model analysis on ZrSiSe. We show that the anomalies in the second band may be spurious, because the first band dominates the Hall magnetoconductivities at T > 80 K, making the carrier type and mobility obtained for the second band from the two-band model analysis unreliable. That is, care must be taken in interpreting these anomalies as evidences for temperature-driven Lifshitz transitions. Our skepticism on the existence of such phase transitions in ZrSiSe is further supported by the validation of the Kohler's rule for magnetoresistances at temperatures below 180 K. This work showcases potential issues in interpreting anomalies in the temperature dependence of the carrier density and mobility derived from the analysis of magnetoconductivities or magnetoresistivities using the conventional two-band model.

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Jing Xu, Yu Wang, Samuel E. Pate, Yanglin Zhu, Zhiqiang Mao, Xufeng Zhang, Xiuquan Zhou, Ulrich Welp, Wai-Kwong Kwok, Duck Young Chung, Mercouri G. Kanatzidis, Zhi-Li Xiao. 2022-12-31. Unreliability of two-band model analysis of magnetoresistivities in unveiling temperature-driven Lifshitz transition. https://doi.org/10.1103/physrevb.107.035104

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