Dirac electron behavior and NMR evidence for topological band inversion in ZrTe5

Abstract

We report ${}^{125}$Te NMR measurements of the topological quantum material ZrTe${}_5$. Spin-lattice relaxation results, well-explained by a theoretical model of Dirac electron systems, reveal that the topological characteristic of ZrTe${}_5$ is $T$-dependent, changing from weak topological insulator to strong topological insulator as temperature increases. Electronic structure calculations confirm this ordering, the reverse of what has been proposed. NMR results demonstrate a gapless Dirac semimetal state occurring at a Lifshitz transition temperature, $T_c=85$ K in our crystals. We demonstrate that the changes in NMR shift at $T_c$ also provide direct evidence of band inversion when the topological phase transition occurs.

5 pages, 4 figures

References in corpus (3)

• Evidence for a Strong Topological Insulator Phase in $\mathrm{ZrT}{\mathrm{e}}_5$
• Lifshitz transition mediated electronic transport anomaly in bulk ZrTe5
• Anomalous hyperfine coupling and nuclear magnetic relaxation in Weyl semimetals

Cited by in corpus (2)

• Site-dependent Local Spin Susceptibility and Low-energy Excitation in a Weyl Semimetal WTe${}_2$
• Robust large-gap topological insulator phase in transition-metal chalcogenide ZrTe${}_4$Se