Colossal magnetoresistance magnetic tunnel junctions grown by molecular-beam epitaxy
Colossal magnetoresistance magnetic tunnel junctions grown by molecular-beam epitaxy
复制标题
DOI：
10.1063/1.126210
复制
发表时间：
2000-03
影响因子：
4
通讯作者：
J. O'Donnell;A. Andrus;Seongshik Oh;E. Colla;J. Eckstein
中科院分区：
文献类型：
--
作者：
J. O'Donnell;A. Andrus;Seongshik Oh;E. Colla;J. Eckstein
利用分子束外延生长技术，我们合成了铁磁体/绝缘体/铁磁体三层异质结构与“巨大”的磁阻材料La 1 − xSrxMnO 3作为铁磁体。在14 K下，在200 Oe的外加磁场下，磁电阻ΔR/R（H）高达450%，并在100 ~ 250 K下保持不变。原位反射高能电子衍射（RHEED）使我们能够将外延生长的质量与磁阻特性相关联。在RHEED中表现出无序迹象的样品在低温输运中也表现出无序效应，并且具有在较低温度下消失的较小的磁阻。
Using molecular-beam-epitaxy growth techniques, we have synthesized ferromagnet/insulator/ferromagnet trilayer heterostructures with the “colossal” magnetoresistance material La1−xSrxMnO3 as the ferromagnet. These trilayer films were fabricated into magnetic tunnel junctions which exhibit magnetoresistance ΔR/R(H) of as much as 450% in 200 Oe applied field at 14 K, and which persists up to ∼250 K. In situ reflection high-energy electron diffraction (RHEED) allows us to correlate the quality of the epitaxial growth with the magnetoresistive properties. Samples which showed signs of disorder in RHEED also exhibit disorder effects in low-temperature transport and have smaller magnetoresistance which vanishes at lower temperatures.