采用固相反应法制备了钙钛矿锰氧化物La0 3Ca0 7Mn1-xWxO3(x=0.08,0.12)样品,通过M-T曲线、M-H曲线、ESR曲线研究了在Mn位掺W对La0 3Ca0 7MnO3电荷有序相的影响以及磁结构的变化过程.结果表明:当x=0.08时,体系存在电荷有序(CO)相,相变温度TcO=275 K,在T＞275 K时体系表现为PM;当温度从275 K下降到230 K,体系在CO相下从自旋无序的顺磁态向自旋有序的反铁磁态转变;在230 K至5 K形成长程反铁磁态,AFM/CO态共存;低温区在AFM/CO态本底中存在一定的铁磁成分.当x=0.12时,体系的CO相已基本融化,150 K以下还残留少量CO相.在高于150K温区表现为顺磁;在低于150K温区从顺磁向铁磁转变.
参考文献
| [1] | 梁燕,彭振生,严国清,郭焕银,蔡之让.钙钛矿氧化物La0.3Ca0.7MnO3的磁性质[J].稀有金属,2005(04):513-516. |
| [2] | Jin S;Teifel T H;Mccormack M et al.[J].Science,1994,264(5157):413. |
| [3] | Dagotto E;Hotta T;Moreo A .[J].PHYSICAL REVIEW,2001,344(1-3):1. |
| [4] | 陈春霞.钙钛矿锰氧化物中电荷有序现象研究进展[J].无机材料学报,2005(01):1-12. |
| [5] | Kao C N R;Arulraj A;Cheetham A K et al.[J].Journal of Physics:Condensed Matter,2000,12(07):R83. |
| [6] | Ramirez A P;Schiffer P;Cheong S W et al.[J].Physical Review Letters,1996,76(17):3188. |
| [7] | Chen C H;Cheong S-W .[J].Physical Review Letters,1996,76(21):4042. |
| [8] | Chen CH.;Hwang HY.;Cheong SW. .CHARGE-ORDERED STRIPES IN LA1-XCAXMNO3 WITH X-GREATER-THAN-0.5[J].Journal of Applied Physics,1997(8 Pt.2a):4326-4330. |
| [9] | Radaelli PG.;Marezio M.;Cheong SW.;Cox DE. .CHARGE, ORBITAL, AND MAGNETIC ORDERING IN LA0.5CA0.5MNO3[J].Physical Review.B.Condensed Matter,1997(5):3015-3023. |
| [10] | Mori S;Chen C H;Cheong S-W .[J].Nature,1998,392:473. |
| [11] | Fernandez-Diaz MT.;Alonso JM.;Herrero E.;Martinez JL. .Structural, thermal, transport, and magnetic properties of the charge-ordered La1/3Ca2/3MnO3 oxide[J].Physical Review.B.Condensed Matter,1999(2):1277-1284. |
| [12] | Radaelli PG.;Capogna L.;Cheong SW.;Marezio M.;Cox DE. .Wigner-crystal and bi-stripe models for the magnetic and crystallographic superstructures of La0.333Ca0.667MnO3[J].Physical Review.B.Condensed Matter,1999(22):14440-14450. |
| [13] | Wang R;Gui J;Zhu Y.[A].北京:北京大学出版社,1999:A41. |
| [14] | Wang R;Gui J;Zhu Y et al.[J].Wuhan Univ J(Natural Sci),1999,4(04):415. |
| [15] | Peng Zhensheng .Large Magnetic Entropy Effect in La_(2/3)Ca_(1/3)MnO_3[J].Journal of Rare Earths,2004(2):232-234. |
| [16] | Vanitha P V;Singh R S;Natarajna S et al.[J].Journal of Solid State Chemistry,1998,137:365. |
| [17] | Maignan A.;Barnabe A.;Martin C.;Hervieu M.;Raveau B.;Damay F. .The effect of Mn-site doping on the magnetotransport properties of CMR manganites[J].Philosophical transactions of the Royal Society. Mathematical, physical, and engineering sciences,1998(1742):1635-1658. |
| [18] | 田宏伟,胡小颖,郑伟涛.钙钛矿锰氧化物Y0.5Ca0.5Mn0.8Fe0.2O3的电子顺磁共振研究[J].稀有金属,2005(05):725-727. |
| [19] | Joshi J P;Gupta R;Sood A K et al.[J].Physical Review B:Condensed Matter,2001,65(02):024410. |
| [20] | Gupta R.;Bhat SV.;Sood AK.;Rao CNR.;Joshi JP. .An electron paramagnetic resonance study of Pr0.6Ca0.4MnO3 across the charge-ordering transition[J].Journal of Physics. Condensed Matter,2000(30):6919-6926. |
| [21] | Tian H W;Zheng W T;Zhao I D et al.[J].CHINESE PHYSICS LETTERS,2005,401(4-6):585. |
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%