MAGNETIC-PROPERTIES OF CU-DOPED POROUS SILICA-GELS - A POSSIBLE CU FERROMAGNET

被引：11

作者：

GARCIA, N

CRESPO, P

HERNANDO, A

BOVIER, C

SERUGHETTI, J

DUVAL, E

机构：

[1] UNIV AUTONOMA MADRID,DEPT FIS MAT CONDENSADA,E-28049 MADRID,SPAIN

[2] UNIV COMPLUTENSE MADRID,RENFE,INST MAGNETISMO APLICADO,LAB SALVADOR VELAYOS,E-28230 MADRID,SPAIN

[3] UNIV LYON 1,DEPT PHYS MAT,F-69622 VILLEURBANNE,FRANCE

[4] UNIV LYON 1,PHYSICOCHIM MAT LUMINISCENTS LAB,F-69622 VILLEURBANNE,FRANCE

来源：

PHYSICAL REVIEW B | 1993年 / 47卷 / 01期

关键词：

D O I：

10.1103/PhysRevB.47.570

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We have studied the magnetic properties of Cu-doped porous silica gels and found that the system seems to be ferromagnetic up to room temperature. This result is fascinating because the amount of Cu ranges from 0.15% to 3% in weight of the total sample. Magnetization, hysteresis loops, and EPR experiments are presented. The paramagnetic signal of the silica gel without doping is negligible. On the other hand, the analysis of the magnetic impurities by x-ray fluorescence shows that these impurities can account for only 10% of the magnetization observed at 300 K.

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页码：570 / 573

页数：4

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