# Possible pressure-induced topological quantum phase transition in the nodal line semimetal ZrSiS

## TL;DR

This study investigates pressure effects on ZrSiS, revealing a possible topological quantum phase transition indicated by changes in quantum oscillation phases, without inducing superconductivity up to 20 GPa.

## Contribution

It provides experimental evidence of a pressure-induced topological phase transition in ZrSiS through resistivity and quantum oscillation measurements.

## Key findings

- Phase change in quantum oscillations suggests a topological transition.
- No superconductivity observed up to 20 GPa.
- Fermi surface area decreases abruptly at transition.

## Abstract

ZrSiS has recently gained attention due to its unusual electronic properties: nearly perfect electron-hole compensation, large, anisotropic magneto-resistance, multiple Dirac nodes near the Fermi level, and an extremely large range of linear dispersion of up to 2 eV. We have carried out a series of high pressure electrical resistivity measurements on single crystals of ZrSiS. Shubnikov-de Haas measurements show two distinct oscillation frequencies. For the smaller orbit, we observe a change in the phase of 0.5, which occurs between 0.16 - 0.5 GPa. This change in phase is accompanied by an abrupt decrease of the cross-sectional area of this Fermi surface. We attribute this change in phase to a possible topological quantum phase transition. The phase of the larger orbit exhibits a Berry phase of pi and remains roughly constant up to 2.3 GPa. Resistivity measurements to higher pressures show no evidence for pressure-induced superconductivity to at least 20 GPa.