Noncuprate layered perovskite Sr 2 RuO 4 is a highly correlated metal and exhibits superconductivity below T c ≈1.35 K. We have newly synthesized related layered ruthenates Ca 2 RuO 4 in two distinct structural phases with substantially different aspect ratios c / a . Electrical and magnetic measurements show that the two phases are insulating antiferromagnets. We argue that both phases of Ca 2 RuO 4 are Mott insulators. The decrease of the 4 d band width in comparison with that of Sr 2 RuO 4 , caused by distortions in the RuO 2 planes, leads to a Mott-Hubbard-type gap.
No takes yet. Share an insight, caveat, or question.
Nakatsuji et al. (1997) studied this question.
Synapse has enriched one closely related paper. Consider it for comparative context: