系统研究了强关联锰氧化物La5/8Ca3/8Mn1-xCoxO3(x=0,0.05)体系的结构和输运特性.结果表明,样品均为很好的正交O′单相结构,Mn位5%Co掺杂明显影响了样品铁磁-顺磁(FM-PM)转变和金属-绝缘体(M-I)转变,M-I转变温度TM-I从未掺杂时的271K降至227K,对应的峰值电阻率ρp增大;随着TM-I的降低,Tc同时降低,磁电阻MR%亦相应增加;La5/8Ca3/8MnO3样品在Tc以下表现出长程铁磁有序态,Mn位5%Co掺杂样品则表现为团簇玻璃型短程铁磁有序行为.证明Co掺杂引起电子的局域化效应乃是导致体系输运行为发生变化的主要原因.同时,从Mn3+-O2--Mn4+双交换(DE)作用和超交换(SE)相互作用机制等出发,对样品的输运行为、CMR效应以及与Co掺杂之间的关联进行了讨论.
参考文献
[1] | R von Helmot;J Wecker;B Holzapfel;L Schultz,,K Samwer .[J].Physical Review Letters,1993,71:2331. |
[2] | G Jeffrey Snyder;Ron Hiskes;Steve Di Carolis;M R Beasley,T H Geballe .[J].Physical Review B,1996,53:14434. |
[3] | Takeshi Obata;Takashi Manako;Yuichi Shimakawa;Yoshimi .[J].Kubo Appl Phys Lett,1999,74:290. |
[4] | C Zener .[J].Physical Review,1951,82:403. |
[5] | D N Argyriou;J F Mitchell;C D Potter;D G Hinks,J D Jorgensen,S D Bader .[J].Physical Review Letters,1996,76:3826. |
[6] | J S Zhou;J B Goodenough .[J].Physical Review Letters,1998,80:2665. |
[7] | N Gayathry;A K Raychaudhuri;S Tiwary;R Gundakaram,A Arulraj,C N R Rao .[J].Physical Review B,1997,56:1345. |
[8] | Y Moritomo;H Kuwahara;Y Tomioka .[J].Physical Review B,1999,55:7549. |
[9] | V Ravindranath;M S Ramachandrarao;G Rangarajan;Y F Lu,J K lein,R Klingeler,S Uhlenbruck,B chner,R Gross .[J].Physical Review B,2001,63:184434. |
[10] | CUI Yu-Jian,JIA Guang-Qiang,HAN Yan-bing,LI Jin-bo,WANG Xin-Yan,GE Hong-Liang,CAO SHI-XUN,ZHANG JIN-CANG.Structural and Transport Properties for Al- and Fe-Doping La0.67Ca0.33MnO3 Perovskite Manganese[J].中国物理快报(英文版),2004(03):540-543. |
[11] | 崔玉建,贾广强,王新燕,韩雁冰,葛洪良,张金仓.La0.67Ca0.33Mn1-xAlxO3体系的结构和输运特性研究[J].中国稀土学报,2004(01):94-98. |
[12] | K Ghosh;S B Ogale;R Ramesh;R L Greene,,T Venkatesan .[J].Physical Review B,1999,59:533. |
[13] | J W Cai;C Wang;B J Shen;J G Zhao ,W S Zhan .[J].Physics Letters,1997,71:1727. |
[14] | F Damay;A Maignan;C Martin;B Raveau .[J].Journal of Applied Physics,1997,82:1485. |
[15] | H Song;W Kim;S Kwon;J Kang .[J].Journal of Applied Physics,2001,89:3398. |
[16] | F Rivadulla;M A Lopez-Quintela;L E Hueso;P Sande,J Rivas,R D Sanchez .[J].Physical Review B,2000,62:5678. |
[17] | P Schiffer;A P Ramirez;W Bao;S-W Cheong .[J].Physical Review Letters,1995,75:3336. |
[18] | D. Verma;A. K. Nigam;T. K. Gundu Rao .Magnetic and transport studies in La_(1-x)Ca_xMn_(0.7)Co_(0.3)O_3 (0.1 <=x<=0.5)[J].Journal of Magnetism and Magnetic Materials,2004(2/3):172-179. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%