Electrical anisotropy and coexistence of structural transitions and superconductivity in $\mathrm{IrT}{\mathrm{e}}_2$

Journal Article · 26 January 2017 · Physical Review B

DOI: https://doi.org/10.1103/physrevb.95.035148 · OSTI ID:1535830

Cao, Guixin ^[1]; Xie, Weiwei ^[2]; Phelan, W. Adam ^[2]; DiTusa, J. F. ^[2]; Jin, Rongying ^[2]

---

1. Louisiana State Univ., Baton Rouge, LA (United States); DOE/OSTI
2. Louisiana State Univ., Baton Rouge, LA (United States)

In this work, we report experimental investigations of the electrical transport, magnetic, and thermodynamic properties of IrTe₂ single crystals. The resistivity, magnetization, and specific heat display anomalies at T_S1 ≈ 283K,T_S2 ≈ 167K, and T_c≈2.5K, corresponding to two structural and one superconducting phase transitions, respectively, demonstrating the coexistence of all of these transitions in high-quality stoichiometric samples. While there is little magnetic anisotropy, a large ab-plane (ρab) and c-axis (ρc) electrical resistivity ratio (ρ_c/ρ_ab≈730 at T=4K) is observed. This two-dimensional (2D) electronic character is further reflected in the disparate temperature dependences of ρ_ab and ρ_c, with ρab exhibiting a Fermi-liquid-like T² dependence below ~25K, while ρc deviates significantly from this standard metallic behavior. In contrast, the magnetization is almost isotropic and negative over a wide temperature range. Furthermore, this can be explained by larger diamagnetism induced by electronic structure reconstruction as probed by the Hall effect and smaller positive contribution from itinerant electrons due to a low density of states (DOS) at the Fermi level. A small electronic specific heat coefficient with γ ≈ 1.8mJ/molK² confirms this assertion. This implies that IrTe₂ is a weakly coupled superconductor. The connection between the superconductivity and the two structural transitions is discussed.

• Research Organization: Louisiana State Univ., Baton Rouge, LA (United States)
• Sponsoring Organization: USDOE; USDOE Office of Science (SC)
• Grant/Contract Number: SC0012432
• OSTI ID: 1535830
• Journal Information: Physical Review B, Journal Name: Physical Review B Journal Issue: 3 Vol. 95; ISSN 2469-9950; ISSN PRBMDO
• Publisher: American Physical Society (APS)Copyright Statement
• Country of Publication: United States
• Language: English