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

TL;DR

The study investigates how hydrostatic pressure tunes the electronic structure and superconductivity in the Dirac semimetal ZrTe$_5$ by combining high-pressure magnetotransport measurements (ρ, MR, ρ_xy) up to 8 GPa with density functional theory calculations that include SOC. It reveals a nonmonotonic evolution of the resistivity peak $T_p$, its disappearance near 6 GPa, and the onset of superconductivity at $T_c=1.8$ K around 8 GPa, accompanied by a dramatic enhancement of MR to ~1400% at low temperature and a switch from electron- to hole-dominated conduction near 6 GPa. The experimental data are supported by DFT showing pressure-induced DOS changes and the emergence of multiple hole pockets crossing the Fermi level starting around 4 GPa, signaling Fermi-surface reconstruction that coincides with a structural transition. These findings illuminate a link between structural/electronic instabilities and superconductivity in ZrTe$_5$, offering insight into pressure-engineered topological states and potential routes to topological superconductivity in Dirac semimetals.

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

Figures (16)

• Figure 1: (a) Optical image of CVT grown ZrTe$_5$ single crystals. (b) Illustration of four probe measurement of transport properties under applied magnetic field B. (c) Schematic views of the sample assembly inside the pyrophyllite cubic gasket. (d) Six anvils compressing the cubic gasket shown in figure (c). Panels (c,d) have been adapted from previous work of our group ref.Cheng2018Uwatoko2008.
• Figure 2: Temperature dependence of resistivity along a-axis of ZrTe$_5$ single crystals under various pressures up to 8 GPa. The application of pressure induces a notable change in resistivity peak (T$_p$ and $\rho$(T$_p$)). The inset figure presents the low-temperature resistivity at 8 GPa, showcasing the superconducting transition at 1.8 K.
• Figure 3: (a)–(h) Magnetic field dependence of magnetoresistance (MR %) of ZrTe$_5$ at varying pressures (1–8 GPa). In panels (b) and (c), pronounced SdH oscillations are observed at low temperatures. The insets of panels (b) and (c) show magnified views of the overlapping data. At 8 GPa (panel h), the MR signal exhibits noticeable degradation, likely arising from experimental constraints associated with the palm cubic anvil cell at high pressure. Asterisks (*) next to temperatures at 1 and 2 GPa indicate data reproduced from our recent study Mishra2025, included here for completeness.
• Figure 4: (a)–(h) Magnetic field dependence of the Hall resistivity ($\rho_{xy}$) of ZrTe$_5$ under varying pressures up to 8 GPa. In the low-pressure regime (1–3 GPa), $\rho_{xy}$ varies nearly linearly with magnetic field (a–c). In the intermediate-pressure regime (4–6 GPa), $\rho_{xy}$ exhibits pronounced non-linear behavior, accompanied by a complete sign reversal at 6 GPa (d–f). In the high-pressure regime (7–8 GPa), the $\rho_{xy}$ signal shows noticeable degradation due to the reduced Hall voltage under extreme pressure conditions (g–h); nevertheless, the Hall sign reversal clearly persists up to 7 GPa. Asterisks (*) next to temperatures at 1 and 2 GPa indicate data reproduced from our recent study Mishra2025.
• Figure 5: Temperature dependence of carrier density (n) (a, c, e) and mobility (µ) (b, d, f) at 1-3 GPa pressure. Here, the solid symbols have been used to denote electron while the open symbols represent holes.