- La$_{1.6}$Ca$_{1.4}$Mn$_2$O$_{7.07}$의 전기전도특성
- ㆍ 저자명
- 정우환
- ㆍ 간행물명
- 요업학회지
- ㆍ 권/호정보
- 1999년|36권 8호|pp.843-847 (5 pages)
- ㆍ 발행정보
- 한국세라믹학회
- ㆍ 파일정보
- 정기간행물| PDF텍스트
- ㆍ 주제분야
- 기타
The dc resistivity dc magnetization and thermopower of layered perovskite La1.6Ca1.4Mn2O7.07 have been studied. The ceramic sample of La1.6Ca1.4Mn2O7.07 undergoes the metal-insulator transition at 120K while a first-order phase transition from a ferromagnetic phase to a paramagnetic phae is observed at 260 K=TC This behavior is quite different from that of the well-known double exchange ferromagnets such as La1-xCaxMnO3 This phenomenon could be understood by considering the effects of the anisotropic double exchange interaction caused by two dimensional Mn-O-Mn networks in this materials. The dc magnetization between 120K and 250K is nearly constant and decreases rapidly with increasing temperature above 250K The measurements of dc resistivity and thermopower indicate that Zener polaron hopping conduction takes place above 260 K.