Structural and magnetic properties in the nonstoichiometric perovskite-type oxides La0.67Sr0.15□0.18MnO3−δ

摘要

Due to many novel phenomena such as colossal magnetoresistance (CMR), magnetocaloric effect (MCE) and possible applications to magnetic devices, hole-doped lanthanum manganites La1−xAxMnO3 family (here A is divalent element such as Ca, Sr, Ba, Pb and etc.) have been intensively studied [1–2]. Their potential for application is based on coupling of spin and charge orders of freedom. Controlling the oxygen content in manganites is crucial in order to obtain well defined magnetic and transport properties [3]. Oxygen content in manganites can be well adjusted experimentally by varying the thermal treatments which is most likely to form the oxygen vacancies in the unit cell. On the other hand, a change of oxygen content may also cause a change in lattice constant. Therefore, one may expect that the properties of manganites with varied oxygen content would be as interesting as those of manganites based on A-site doping.