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通过传统固相反应法制备了钙钛矿锰氧化物（La1-xEux）4/3Sr5/3Mn2O7（x=0，0.15）多晶样品，并且对其磁性和电性进行了研究. 磁性测量表明：随着温度的降低，样品经历了一个复杂的转变过程，在温度为T*时经历二维短程铁磁有序转变，在温度为TC时进入三维长程铁磁态. 随着Eu的掺杂，T*和TC减小，并且样品（La0.85Eu0.15）4/3Sr5/3Mn2O7 在低温区表现出自旋玻璃行为. 电性质测量表明：在母体La4/3Sr5/3Mn2O7中La 位掺杂Eu后电阻率明显变大，金属绝缘转变温度TMI降低，磁电阻峰值增大. 这些影响归因于较小的Eu3+离子替代La3+离子导致平均离子半径减小，晶格发生畸变. 此外，较小的Eu3+离子优先占据层间岩盐层的R-site，使La3+，Sr3+，Eu3+离子在（La0.85Eu0.15）4/3Sr5/3Mn2O7 中的分布更加有序，所以x=0.15的样品的ρ-T曲线只有一个峰.The samples (La1-xEux)4/3Sr5/3Mn2O7 (x=0, 0.15) were prepared by the traditional solid-state reaction, and their magnetic and electrical properties were investigated. The magnetzation measurement reveals that as temperature lowers, all the samples undergo a complex magnetic transition process: they transform from the two-dimensional short-range ferromagnetic order at T* into the three-dimensional long-range ferromagnetic state at TC. With the increase of Eu doping, T* and TC are both reduced, and the sample (La0.85Eu0.15)4/3Sr5/3Mn2O7 exhibits spin-glass-like behaviour in a low temperature region. Electrical property measurements show that with the increase of Eu concentration, resistivity sharply increases, the metal-insulator transition temperature decreases and the magnetoresistance peak increases. These effects are attributed to the decrease of the average ionic radius diminution and the lattice distortion due to the substitution of the smaller Eu3+ ions for La3+ ions. In addition, the small-sized Eu3+ ion preferentially occupies the R site in the rock-salt layer, then the distributions of La3+, Sr3+, Eu3+ ions in the sample (La0.85Eu0.15)4/3Sr5/3Mn2O7 should be more orderly, so there is only one peak in the ρ-T curve of the sample with x=0.15.
[1] Imada M, Fujimori A, Tokura Y 1998 Rev. Mod. Phys. 70 1039
[2] Zhao J J, Xing R, Lu Y, Haosi B Y, Zhao M Y, Jin X, Zheng L, Ning W, Sun Y, Cheng Z H 2008 Chin. Phys. B 17 2721
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[4] Wang G Y, Guo H Y, Mao Q, Yang G, Peng Z S 2010 Acta Phys. Sin. 59 8883 (in Chinese) [王桂英, 郭焕银, 毛强, 杨刚, 彭振生 2010 59 8883]
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[6] Han L A, Chen C L, Dong H Y, Wang J Y, Gao G M, Luo B C 2008 Acta Phys. Sin. 57 541 (in Chinese) [韩立安, 陈长乐, 董慧迎, 王建元, 高国棉, 罗炳成 2008 57 541]
[7] Chattopadhyay S, Giri S, Majumdar S 2012 J. Appl. Phys. 112 083915
[8] Kimura T, Tomioka Y, Kuwahara H, Asamitsu A, Tamura M, Tokura Y 1996 Science 274 1698
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[10] Yang R F, Sun Y, He W, Li Q A, Cheng Z H 2007 Appl. Phys. Lett. 90 032502
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[13] Wang A H, Liu Y, Zhang Z Y, Long Y, Cao G H 2004 Solid State Commun. 130 293
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[15] Liu L, Xia Z C, Yuan S L 2006 Mater. Sci. Eng. B 127 55
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[1] Imada M, Fujimori A, Tokura Y 1998 Rev. Mod. Phys. 70 1039
[2] Zhao J J, Xing R, Lu Y, Haosi B Y, Zhao M Y, Jin X, Zheng L, Ning W, Sun Y, Cheng Z H 2008 Chin. Phys. B 17 2721
[3] Zhao J J, Lu Y, Haosi B Y, Xing R, Yang R F, Li Q A, Sun Y, Cheng Z H 2008 Chin. Phys. B 17 2717
[4] Wang G Y, Guo H Y, Mao Q, Yang G, Peng Z S 2010 Acta Phys. Sin. 59 8883 (in Chinese) [王桂英, 郭焕银, 毛强, 杨刚, 彭振生 2010 59 8883]
[5] Moritomo Y, Asamitsu A, Kuwahara H, Tokura Y 1996 Nature 380 141
[6] Han L A, Chen C L, Dong H Y, Wang J Y, Gao G M, Luo B C 2008 Acta Phys. Sin. 57 541 (in Chinese) [韩立安, 陈长乐, 董慧迎, 王建元, 高国棉, 罗炳成 2008 57 541]
[7] Chattopadhyay S, Giri S, Majumdar S 2012 J. Appl. Phys. 112 083915
[8] Kimura T, Tomioka Y, Kuwahara H, Asamitsu A, Tamura M, Tokura Y 1996 Science 274 1698
[9] Argyriou D N, Mitchell J F, Radaelli P G, Bordallo H N, Cox D E, Medarde M, Jorgensen J D 1999 Phys. Rev. B 59 8695
[10] Yang R F, Sun Y, He W, Li Q A, Cheng Z H 2007 Appl. Phys. Lett. 90 032502
[11] Dho J H, Kim W S, Hur N H 2001 Phys. Rev. B 65 024404
[12] Zhang J, Wang F W, Zhang P L, Yan Q W 2000 Mater. Sci. Eng. B 76 6
[13] Wang A H, Liu Y, Zhang Z Y, Long Y, Cao G H 2004 Solid State Commun. 130 293
[14] Asano H, Hayakawa J, Matsui M 1997 Phys. Rev. B 56 5395
[15] Liu L, Xia Z C, Yuan S L 2006 Mater. Sci. Eng. B 127 55
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