Pressure induced electronic band evolution and observation of superconductivity in the Dirac semimetal ZrTe5

TL;DR

This study explores how applying pressure to ZrTe5 alters its electronic structure, leading to superconductivity at high pressure, supported by experimental magnetotransport data and density functional theory calculations.

Contribution

It provides a detailed pressure-dependent analysis of ZrTe5's electronic evolution and links structural changes to the emergence of superconductivity.

Findings

Superconductivity appears below 1.8 K at 8 GPa.

Pressure causes significant Fermi surface reconstruction.

Magnetoresistance is dramatically enhanced up to 1400%.

Abstract

We report a comprehensive investigation of the pressure effects on the magnetotransport properties of the topological material ZrTe5 within 1 to 8 GPa pressure range. With increasing pressure, the characteristic peak (Tp) in its electrical resistivity first shifts to higher temperature and then moves quickly towards the lower temperature before disappearing eventually at 6 GPa. Beyond 6 GPa, the system exhibits metallic behavior across the entire temperature range, and superconductivity emerges below Tc = 1.8 K at 8 GPa. Based on the systematic magnetotransport measurement under pressure, we demonstrate that the superconductivity occurs following a significant electronic structure modulation possibly due to pressure induced structural changes near 6 GPa, which coincides with dramatic enhancement of the magnetoresistance (MR) reaching up to 1400 percent. Our experimental results are substantiated by density functional theory calculations as the application of pressure drastically alters the density of states near the Fermi level. Notably, multiple hole pockets emerge at the Fermi level from 4 GPa onward, and their contributions are further enhanced with increasing pressure. The combined experimental and theoretical investigation reveals a comprehensive evolution of electronic structure of Dirac semimetal ZrTe5 under pressure and suggest a possible link between the Fermi surface reconstruction in the pressure range of structural transition and emergence of superconductivity