Spin Valve Effect and Magnetoresistivity in Single Crystalline Ca3Ru2O7
Abstract
The laminar perovskite Ca3Ru2O7 naturally forms ferromagnetic double layers of alternating moment directions, as in the spin-valve superlattices. The mechanism of the huge magnetoresistive effect in the material has been controversial due to a lack of clear understanding of various magnetic phases and phase transitions. In this neutron diffraction study in a magnetic field, we identify four different magnetic phases in Ca3Ru2O7 and determine all first-order and second-order phase transitions between them. The spin-valve mechanism then readily explains the dominant magnetoresistive effect in Ca3Ru2O7.
- Publication:
-
Physical Review Letters
- Pub Date:
- June 2008
- DOI:
- arXiv:
- arXiv:0802.0713
- Bibcode:
- 2008PhRvL.100x7203B
- Keywords:
-
- 75.25.+z;
- 72.20.My;
- 75.30.Kz;
- 75.47.Gk;
- Spin arrangements in magnetically ordered materials;
- Galvanomagnetic and other magnetotransport effects;
- Magnetic phase boundaries;
- Colossal magnetoresistance;
- Condensed Matter - Strongly Correlated Electrons
- E-Print:
- 4 pages, 5 figures