Antiferromagnetic correlations in the metallic strongly correlated transition metal oxide LaNiO3

Abstract

The material class of rare earth nickelates with high Ni3+ oxidation state is generating continued interest due to the occurrence of a metal-insulator transition with charge order and the appearance of non-collinear magnetic phases within this insulating regime. The recent theoretical prediction for superconductivity in LaNiO3 thin films has also triggered intensive research efforts. LaNiO3 seems to be the only rare earth nickelate that stays metallic and paramagnetic down to lowest temperatures. So far, centimeter-sized impurity-free single crystal growth has not been reported for the rare earth nickelates material class since elevated oxygen pressures are required for their synthesis. Here, we report on the successful growth of centimeter-sized LaNiO3 single crystals by the floating zone technique at oxygen pressures of up to 150 bar. Our crystals are essentially free from Ni2+ impurities and exhibit metallic properties together with an unexpected but clear antiferromagnetic transition.

Local metallic and structural properties of the strongly correlated metal LaNiO3 using 8Li β–NMR

“…While it is widely accepted that LNO remains a metal to low temperature, the occurrence of static antiferromagnetism (AF) was recently suggested from new data in a single crystal at T N ≈ 157 K. 16 In contrast, we have no evidence of magnetic ordering at this temperature, either from the resonance line or 1/T 1 , in agreement with recent data suggesting that the AF is due to an oxygen deficient phase. 17 We turn now to the sample dependent deviation from the Korringa dependence of 1/T 1 above 200 K. This bifurcation coincides with a small change in the Ni-O-Ni angle from structural studies on powders.…”

Observation of an antiferromagnetic quantum critical point in high-purity LaNiO3

“…The data can be fit well to a T 2 dependence for B = 9 T and 18 T, with corresponding A coefficients in ρ(T ) being 8 × 10 −3 and 7 × 10 −3 µΩ cm K −2 , respectively. These values of A are about 3 to 4 times larger than those, ∼ 2 × 10 −3 µΩ cm K −2 , reported for LNO previously 13,15,26 , which is suggestive of enhanced scattering near the QCP. We note that this crossover to LFL in the resistivity under a magnetic field is seen only in samples with RRR ≥ 18.…”

Breathing distortions in the metallic, antiferromagnetic phase of LaNiO$_3$

“…These samples did not exhibit any structural or magnetic transition, but their magnetic susceptibility showed a broad maximum around 200 K. A small anomaly had also been observed around this temperature in earlier measurements of the magnetic susceptibility on polycrystalline samples [30]. However, the samples grown by Guo et al under the oxygen pressure of 130-150 bar showed an antiferromagnetic transition at 157 K with an ordering wave vector of ( 1 4 , 1 4 , 1 4 ) c in the pseudocubic notation [32]. The antiferromagnetic phase remained in the rhombohedral R3c structure and continued to exhibit a metallic behavior.…”