Abstract
A nanoscale ordered perovskite cobaltite, which consists of 90° ordered domains of the layered “112” , has been evidenced by high resolution-transmission electron microscopy. This form, such as the disordered and ordered , exhibits a ferromagnetic transition at . However, it differs from the two previous forms by its strong magnetic anisotropy and, correlatively, by its high value of coercivity at low temperature. We suggest that this behavior originates from the locking of magnetic spins in the 90° oriented nanodomain. Moreover, one observes a semimetal to semimetal transition at with a maximum magnetoresistance of at this temperature.
- Received 23 July 2007
DOI:https://doi.org/10.1103/PhysRevB.76.184432
©2007 American Physical Society