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arXiv · 2206.13957

Engineering a pure Dirac regime in ZrTe$_5$

Jorge I. Facio·Elisabetta Nocerino·Ion Cosma Fulga·Rafal Wawrzynczak·Joanna Brown·Genda Gu·Qiang Li·Martin Mansson·Yasmine Sassa·Oleh Ivashko·Martin v. Zimmermann·Felix Mende·Johannes Gooth·Stanislaw Galeski·Jeroen van den Brink·Tobias Meng
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Abstract

Real-world topological semimetals typically exhibit Dirac and Weyl nodes that coexist with trivial Fermi pockets. This tends to mask the physics of the relativistic quasiparticles. Using the example of ZrTe5, we show that strain provides a powerful tool for in-situ tuning of the band structure such that all trivial pockets are pushed far away from the Fermi energy, but only for a certain range of Van der Waals gaps. Our results naturally reconcile contradicting reports on the presence or absence of additional pockets in ZrTe$_5$, and provide a clear map of where to find a pure three-dimensional Dirac semimetallic phase in the structural parameter space of the material.

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Jorge I. Facio, Elisabetta Nocerino, Ion Cosma Fulga, Rafal Wawrzynczak, Joanna Brown, Genda Gu, Qiang Li, Martin Mansson, Yasmine Sassa, Oleh Ivashko, Martin v. Zimmermann, Felix Mende, Johannes Gooth, Stanislaw Galeski, Jeroen van den Brink, Tobias Meng. 2022-06-28. Engineering a pure Dirac regime in ZrTe$_5$. https://doi.org/10.21468/scipostphys.14.4.066

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