Hydrostatic pressure effects on the magnetic susceptibility of ruthenium oxide Sr 3Ru 2O 7: evidence for pressure-enhanced antiferromagnetic instability

• Published in: Solid state communications Vol. 130; no. 5; pp. 341 - 346
• Main Authors: Sushko, Yuri V., DeHarak, Bruno, Cao, Gang, Shaw, G., Powell, D.K., Brill, J.W.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2004
• Subjects: A. Ruthenates; D. Antiferromagnetism; D. Ferromagnetism; D. SQUID magnetometry; E. High pressure; 62.50.+p; D. SQUID magnetometry; 75.40.Cx; D. Ferromagnetism; D. Antiferromagnetism; A. Ruthenates; 75.30.Kz; E. High pressure
• ISSN: 0038-1098; 1879-2766
• DOI: 10.1016/j.ssc.2004.02.010

Hydrostatic pressure effects on the temperature- and magnetic field dependencies of the in-plane and out-of-plane magnetization of the bi-layered perovskite Sr 3Ru 2O 7 have been studied by SQUID magnetometer measurements under a hydrostatic helium-gas pressure. The anomalously enhanced low-temperature value of the paramagnetic susceptibility has been found to systematically decrease with increasing pressure. The effect is accompanied by an increase of the temperature T max of a pronounced peak of susceptibility. Thus, magnetization measurements under hydrostatic pressure reveal that the lattice contraction in the structure of Sr 3Ru 2O 7 promotes antiferromagnetism and not ferromagnetism. The effects can be explained by the enhancement of the inter-bi-layer antiferromagnetic spin coupling, driven by the shortening of the superexchange path, and suppression, due to the band-broadening effect, of competing itinerant ferromagnetic correlations.