Conductivity and magnetoresistance of La0.7Ce0.3MnO3−δ thin films under photoexcitation
Conductivity and magnetoresistance of La0.7Ce0.3MnO3−δ thin films under photoexcitation
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光激发下La0 7Ce0 3MnO3âδ薄膜的电导率和磁阻
DOI：
10.1088/0953-8984/27/2/025503
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
L. M. Eng
中科院分区：
文献类型：
--
作者：
A. Thiessen;E. Beyreuther;R. Werner;R. Kleiner;D. Koelle;L. M. Eng
在SrTiO单晶衬底上生长了不同厚度、不同CeO相偏析程度和不同氧缺陷程度的LaCeMnO薄膜，比较研究了它们在光激发下的光谱和温度依赖性光电导（PC）和磁电阻（MR）行为.虽然生长的薄膜是不敏感的光激发，氧还原似乎是一种有效的方式来降低膜电阻，但膜厚度被发现发挥次要作用。然而，从PC的光谱行为的评估和在照明下LCeMO/衬底样品与裸衬底的MR的比较中，我们发现光电导数据不仅反映了来自（i）膜中的光生电荷载流子和（ii）从光电导衬底注入的载流子的贡献（如从早期的作品得出的结论），而且（iii）一个决定性的平行光电导SrTiO基板。此外-也通过分析的MR特性-一个强大的电阻效应的意外发生在样品中的最高程度的CeO偏析和氧不足，可以归因于电阻的SrTiO基板以及。结果表明，一个关键的反思，并可能重新解释以前的几个光电导和电阻的锰氧化物薄膜SrTiO的调查。
LaCeMnOthin films of different thicknesses, degrees of CeO-phase segregation and oxygen deficiency, grown on SrTiOsingle crystal substrates, were comparatively investigated with respect to both their spectral and temperature-dependent photoconductivity (PC) and their magnetoresistance (MR) behaviour under photoexcitation. While as-grown films were insensitive to optical excitation, oxygen reduction appeared to be an effective way to decrease the film resistance, but the film thickness was found to play a minor role. However, from the evaluation of the spectral behaviour of the PC and the comparison of the MR of the LCeMO/substrate-samples with a bare substrate under illumination we find that the photoconductivity data reflects not only contributions from (i) photogenerated charge carriers in the film and (ii) carriers injected from the photoconductive substrate (as concluded from earlier works), but also (iii) a decisive parallel photoconduction in the SrTiOsubstrate. Furthermore -- also by analyzing the MR characteristics -- the unexpected occurence of a strong electroresistive effect in the sample with the highest degree of CeOsegregation and oxygen deficiency could be attributed to the electroresistance of the SrTiOsubstrate as well. The results suggest a critical reconsideration and possibly a reinterpretation of several previous photoconductivity and electroresistance investigations of manganite thin films on SrTiO.
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影响因子：
3.7
作者：
Beyreuther, E;Grafström, S;Dörr, K
通讯作者：
Dörr, K
影响因子：
3.7
作者：
R. Werner;C. Raisch;V. Leca;V. Ion;S. Bals;G. Tendeloo;T. Chass'e;R. Kleiner;D. Koelle
通讯作者：
R. Werner;C. Raisch;V. Leca;V. Ion;S. Bals;G. Tendeloo;T. Chass'e;R. Kleiner;D. Koelle
DOI：
10.1016/j.mseb.2010.12.014
发表时间：
2011-03-25
影响因子：
3.6
作者：
Beyreuther, E.;Thiessen, A.;Eng, L. M.
通讯作者：
Eng, L. M.
影响因子：
4
作者：
Fiebig, M;Miyano, K;Tokura, Y
通讯作者：
Tokura, Y
DOI：
10.1023/a:1007760202272
发表时间：
2000-04
期刊：
Journal of Superconductivity
影响因子：
--
作者：
A. Gilabert;R. Cauro;M. Medici;J. Grenet;H. Wang;Y. Hu;Qi Li
通讯作者：
A. Gilabert;R. Cauro;M. Medici;J. Grenet;H. Wang;Y. Hu;Qi Li