Optimized growth of large-size, high quality $\text{ZrTe}_5$ single crystals enabling clear quantum oscillations in electrical transport

TL;DR

This paper presents an optimized synthesis method for high-quality ZrTe₅ single crystals, enabling clear quantum oscillations and facilitating the study of topological phase transitions and Dirac fermion physics.

Contribution

The authors develop a Te-flux growth technique that produces large, high-purity ZrTe₅ crystals with superior electronic properties, overcoming previous challenges caused by defects and stoichiometric variations.

Findings

Low magnetic field for quantum oscillations ($ ext{B}_{int} ext{ approx. } 0.38 T$)

Ultra-high mobility of $5.58 imes 10^5$ cm$^2$V$^{-1}$s$^{-1}$

Access to quantum limit at about 1.3 T

Abstract

Quantum oscillation with nontrivial Berry phase is one of the characteristics of topological materials. As a Dirac semimetal candidate, zirconium pentatelluride ($\text{ZrTe}_5$) stands out as an intriguing material for investigating topological phase transitions and Dirac fermion physics; however, the extreme sensitivity of its electronic properties to stoichiometric variations and crystalline defects has hindered consistent experimental observation. Here, we report an optimized Te-flux synthesis method designed to produce centimeter-scale, high-quality single crystals meanwhile minimizing extrinsic carrier contamination. Comprehensive morphology, structural and chemical characterizations, including scanning electron microscopy, Laue backscattering and Rietveld refinement, confirm a high-purity $Cmcm$ phase with excellent crystallinity. Furthermore, magnetotransport measurements reveal a remarkably low Shubnikov-de Haas oscillation onset field ($B_{int} \approx 0.38$ T) with an ultra-high mobility of $5.58\times10^5$cm$^2$V$^{-1}$s$^{-1}$ and access to the the quantum limit at $B \approx 1.3$ T, attesting to the superior crystalline quality and the efficacy of this growth optimization. These results demonstrate that growth control is crucial for stabilizing intrinsic electronic behavior in $\text{ZrTe}_5$, establishing a robust platform for exploring topological phase transitions and exotic quantum phenomena in topological semimetals.