Anomalous in-plane magnetoresistance of electron-doped cuprate La2−xCexCuO4±δ
journal contributionposted on 08.06.2017, 12:51 by H.S. Yu, G. He, Yanli Jia, X. Zhang, J. Yuan, Beiyi Zhu, Anna KusmartsevaAnna Kusmartseva, Feodor Kusmartsev, K. Jin
We report systematic in-plane magnetoresistance measurements on the electron-doped cuprate La2−xCexCuO4±δ thin films as a function of Ce doping and oxygen content in the magnetic field up to 14T. A crossover from negative to positive magnetoresistance occurs between the doping level x = 0.07 and 0.08. Above x = 0.08, the positive magnetoresistance effect appears, and is almost indiscernible at x = 0.15. By tuning the oxygen content, the as-grown samples show negative magnetoresistance effect, whereas the optimally annealed ones display positive magnetoresistance effect at the doping level x = 0.15. Intriguingly, a linear-field dependence of in-plane magnetoresistance is observed at the underdoping level x = 0.06, the optimal doping level x = 0.1 and slightly overdoping level x = 0.11. These anomalies of in-plane magnetoresistance may be related to the intrinsic inhomogeneity in the cuprates, which is discussed in the framework of network model.
This work was supported by the National Key Basic Research Program of China (Grant Nos. 2015CB921000, and 2016YFA0300301), the National Natural Science Foundation of China (Grant Nos. 11674374, and 11474338), and the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (Grant No. QYZDB-SSW-SLH008)