Jin Yuan, Cui Xiao-Peng, Han Wei-Hua, Cao Shi-Xun, Gao Yu-Ze, Zhang Jin-Cang
Materials Genome Institute and College of Science, Shanghai University, Shanghai 200444, China.
Phys Chem Chem Phys. 2015 May 21;17(19):12826-32. doi: 10.1039/c5cp00842e.
We report the low-temperature resistance upturn in sandwiched structures of La2/3Sr1/3MnO3/ZrO2/La2/3Sr1/3MnO3 and La2/3Sr1/3MnO3/LaMnO3/La2/3Sr1/3MnO3, while it disappeared when the interlayer was replaced by YBa2Cu3O7. The experimental data have been analyzed qualitatively and quantitatively. The results show that the low temperature resistance upturn is mainly due to the quantum correction effects driven by the weak localization and the electron-electron interaction in such a strongly correlated system, and the contribution of each factor varies with grain boundaries. Moreover, the resistance upturns are suppressed by a local magnetic field. These findings will help to further understand the physical mechanism of low-temperature resistance upturn in colossal magnetoresistance manganites. Furthermore, it is also helpful to reveal the intrinsic transport mechanism at the interfaces of semiconductor/ferromagnetism and antiferromagnetism/ferromagnetism.
我们报道了La2/3Sr1/3MnO3/ZrO2/La2/3Sr1/3MnO3和La2/3Sr1/3MnO3/LaMnO3/La2/3Sr1/3MnO3夹心结构中的低温电阻上升现象，而当中间层被YBa2Cu3O7取代时，该现象消失。对实验数据进行了定性和定量分析。结果表明，低温电阻上升主要归因于在这种强关联系统中由弱局域化和电子-电子相互作用驱动的量子修正效应，并且每个因素的贡献随晶界而变化。此外，局部磁场抑制了电阻上升。这些发现将有助于进一步理解巨磁电阻锰氧化物中低温电阻上升的物理机制。此外，这对于揭示半导体/铁磁性和反铁磁性/铁磁性界面处的本征输运机制也很有帮助。
