Long-time mystery in cobalt oxides
Wednesday, August 3, 2011 - 12:30
in Physics & Chemistry
The existence of an intermediate-spin (IS) state in cobalt oxides has long been a subject of dispute. A recent resonant X-ray scattering experiment has clearly demonstrated Co3+ eg orbital ordering in Sr3YCo4O10.5, which has the highest ferromagnetic transition temperature among perovskite-type cobalt oxides. This result provides not only a clue to understanding the magnetism but also the first clear evidence of the existence of an IS state in Co3+. This discovery is expected to open a new field of materials physics, which will combine the IS state concept with many interesting magnetic and electric properties.