Markna J H, Vachhani P S, Kuberkar D G, Shah N A, Misra P, Singh B N, Kukreja L M, Rana D S
Department of Physics, Saurashtra University, Rajkot 360005, India.
J Nanosci Nanotechnol. 2009 Sep;9(9):5687-91. doi: 10.1166/jnn.2009.1182.
We report the use of non-magnetic Al2O3 nano particles deposited between two ferromagnetic La0.5Pr0.2Sr0.3MnO3 (LPSMO) manganite layers with an aim to improve the electronic and magnetotransport properties of the layered supper lattice grown on single crystal STO(100) substrate using Pulsed Laser Deposition (PLD) technique. We studied the electronic-transport and magnetotransport properties of this system wherein Al2O3 particles are expected to act as insulating scattering centers between two ferromagnetic LPSMO layers. The scattering due to additional scattering centers (insulating Al2O3 nano particles) could be controlled by application of external field, resulting in high magnetoresistance (MR) approximately 72% as compared to pristine LPSMO film (MR approximately 51%) at temperature close to their T(M) values. In addition, incorporation of nanostructured Al2O3 barrier between the two ferromagnetic LPSMO layers results in a 2-3 fold increase in the values of temperature coefficient of resistance (TCR) and the field coefficient of resistance (FCR) as compared to pristine LPSMO film, suggesting the use of such nanoengineered manganite layered structure for better device application.
我们报道了在两个铁磁层状钙钛矿La0.5Pr0.2Sr0.3MnO3（LPSMO）锰氧化物层之间沉积非磁性Al2O3纳米颗粒的应用，目的是改善使用脉冲激光沉积（PLD）技术在单晶STO(100)衬底上生长的层状超晶格的电子和磁输运特性。我们研究了该系统的电子输运和磁输运特性，其中Al2O3颗粒有望作为两个铁磁LPSMO层之间的绝缘散射中心。由于额外散射中心（绝缘Al2O3纳米颗粒）引起的散射可以通过施加外部磁场来控制，与原始LPSMO薄膜相比，在接近其居里温度（TC）值的温度下，产生了约72%的高磁电阻（MR）（原始LPSMO薄膜的MR约为51%）。此外，在两个铁磁LPSMO层之间引入纳米结构的Al2O3势垒，与原始LPSMO薄膜相比，电阻温度系数（TCR）和电阻场系数（FCR）的值增加了2 - 3倍，这表明这种纳米工程锰氧化物层状结构可用于更好的器件应用。
