Regensburg 2019 – wissenschaftliches Programm

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TT: Fachverband Tiefe Temperaturen

TT 54: Correlated Electrons: Complex Oxides and Other Materials

TT 54.5: Vortrag

Donnerstag, 4. April 2019, 10:30–10:45, H22

High-pressure floating-zone growth of LaNiO₃ single crystals — •Kaustav Dey, Mahmoud M.Abdel-Hafiez, and Rüdiger Klingeler — Kirchhoff Institute for Physics, Heidelberg University, Germany

LaNiO₃ is known to be a correlated metal in the vicinity of a bandwidth controlled metal-insulator transition. A variety of experimental studies on polycrystalline LaNiO₃ have indicated it to be a Pauli paramagnetic metal. Recently, the successful growth of LaNiO₃ single crystals was published [1,2]. Suprisingly, Guo et. al. have reported that LaNiO₃ has an antiferromagnetic metallic ground state [2]. We discuss the successful growth and characterization of centimeter-sized single crystals of LaNiO₃ by means of the floating zone technique at oxygen pressures of up to 80 bar. Indeed, magnetisation and specific heat data on several LaNiO₃ single crystals grown at 40 bar show the presence of a anomaly in the range 150-160 K similar to what is reported in Ref. [2]. In contrast, no anomaly was observed in the crystals grown at 80 bar in agreement with Ref. [1]. We infer that higher pressure leads to better crystal quality in terms of phase purity and that the anomaly associated with antiferromagnetism reported in LaNiO₃ single crystals may not be of intrinsic nature.
J. Zhang et al., Cryst. Growth Des. 17, 2730 (2017)
H. Guo et al., Nat. Comm. 9:43 (2018).