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arXiv · 2211.16711

Revealing temperature evolution of the Dirac band in ZrTe$_5$ via magneto-infrared spectroscopy

Yuxuan Jiang·Tianhao Zhao·Luojia Zhang·Qiang Chen·Haidong Zhou·Mykhaylo Ozerov·Dmitry Smirnov·Zhigang Jiang
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Abstract

We report the temperature evolution of the Dirac band in semiconducting zirconium pentatelluride (ZrTe$_5$) using magneto-infrared spectroscopy. We find that the band gap is temperature independent at low temperatures and increases with temperature at elevated temperatures. Although such an observation seems to support a weak topological insulator phase at all temperatures and defy the previously reported topological phase transition (TPT) at an intermediate temperature in ZrTe$_5$, we show that it is also possible to explain the observation by considering the effect of conduction-valence band mixing and band inversion with a strong topological insulator phase at low temperatures. Our work provides an alternative picture of the band gap evolution across TPT.

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Yuxuan Jiang, Tianhao Zhao, Luojia Zhang, Qiang Chen, Haidong Zhou, Mykhaylo Ozerov, Dmitry Smirnov, Zhigang Jiang. 2023-07-27. Revealing temperature evolution of the Dirac band in ZrTe$_5$ via magneto-infrared spectroscopy. https://doi.org/10.1103/physrevb.108.l041202

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