# Disruption of the accidental Dirac semimetal state in ZrTe$_{5}$ under hydrostatic pressure

## TL;DR

This study investigates how hydrostatic pressure affects the magnetotransport properties of ZrTe$_{5}$, revealing the disruption of its accidental Dirac semimetal state and evolution towards isotropic electronic behavior.

## Contribution

It provides experimental evidence that pressure breaks the Dirac node in ZrTe$_{5}$, altering its topological and electronic properties, which was not previously established.

## Key findings

- Pressure enhances resistivity anomaly but T* remains unchanged.
- Quantum oscillation phase shifts from topological nontrivial to trivial around 2 GPa.
- ZrTe$_{5}$ transitions from anisotropic to nearly isotropic electronic system under pressure.

## Abstract

We study the effect of hydrostatic pressure on the magnetotransport properties of the zirconium pentatelluride. The magnitude of resistivity anomaly gets enhanced with increasing pressure, but the transition temperature $T^{\ast}$ is almost independent of it. In the case of H $\parallel$ $b$, the quasi-linear magnetoresistance decreases drastically from 3300$\%$ (9 T) at ambient pressure to 400$\%$ (14 T) at 2.5 GPa. Besides, the change of the quantum oscillation phase from topological nontrivial to trivial is revealed around 2 GPa. Both demonstrate that the pressure breaks the accidental Dirac node in ZrTe$_{5}$. For H $\parallel$ $c$, in contrast, subtle changes can be seen in the magnetoresistance and quantum oscillations. In the presence of pressure, ZrTe$_{5}$ evolves from a highly anisotropic to a nearly isotropic electronic system, which accompanies with the disruption of the accidental Dirac semimetal state. It supports the assumption that ZrTe$_{5}$ is a semi-3D Dirac system with linear dispersion along two directions and a quadratic one along the third.