Magnetic properties, relaxation, and quantum tunneling in CoFe2O4 nanoparticles embedded in potassium silicate

被引:78
作者
Zhang, XX [1 ]
Hernandez, JM [1 ]
Tejada, J [1 ]
Ziolo, RF [1 ]
机构
[1] XEROX CORP,WILSON CTR RES & TECHNOL,WEBSTER,NY 14580
来源
PHYSICAL REVIEW B | 1996年 / 54卷 / 06期
关键词
D O I
10.1103/PhysRevB.54.4101
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
We report magnetic properties and magnetic relaxation phenomena in a sample comprised of nanocrystalline CoFe2O4 (similar to 97%)+gamma-Fe2O3(similar to 3%) and polymer in potassium silicate (as magnetic glass) nanoparticle systems in which two very different barrier distributions contributed to the relaxation behavior. We have demonstrated experimentally that only energy barrier distributions and the thermal activation process could not account for a plateau in the viscosity data at low temperatures. Quantum tunneling of magnetization is suggested below similar to 3 K.
引用
收藏
页码:4101 / 4106
页数:6
相关论文
共 19 条
[11]   LOW-FIELD MAGNETIC-RELAXATION EFFECTS IN HIGH-TC SUPERCONDUCTORS SR-LA-CU-O AND BA-LA-CU-O [J].
MOTA, AC ;
POLLINI, A ;
VISANI, P ;
MULLER, KA ;
BEDNORZ, JG .
PHYSICAL REVIEW B, 1987, 36 (07) :4011-4013
[12]   STUDIES OF HYSTERESIS IN MN12AC [J].
PAULSEN, C ;
PARK, JG ;
BARBARA, B ;
SESSOLI, R ;
CANESCHI, A .
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1995, 140 :1891-1892
[13]   NONTHERMAL VISCOSITY IN MAGNETS - QUANTUM TUNNELING OF THE MAGNETIZATION [J].
TEJADA, J ;
ZHANG, XX ;
BALCELLS, L .
JOURNAL OF APPLIED PHYSICS, 1993, 73 (10) :6709-6714
[14]   QUANTUM RELAXATION IN RANDOM MAGNETS [J].
TEJADA, J ;
ZHANG, XX .
PHYSICAL REVIEW B, 1993, 47 (22) :14977-14987
[15]   EXPERIMENTS IN QUANTUM MAGNETIC-RELAXATION [J].
TEJADA, J ;
ZHANG, XX .
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1995, 140 :1815-1818
[16]   QUANTUM EXPONENTIAL RELAXATION OF ANTIFERROMAGNETIC DOMAIN-WALLS IN FETBO3 SINGLE-CRYSTAL [J].
ZHANG, XX ;
TEJADA, J ;
ROIG, A ;
NIKOLOV, O ;
MOLINS, E .
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS, 1994, 137 (03) :L235-L238
[17]   EXPERIMENTAL-EVIDENCE OF QUANTUM TUNNELING OF 2D VORTICES UP TO 10-K IN BULK TL2BA2CA2CU3O10 SUPERCONDUCTOR [J].
ZHANG, XX ;
GARCIA, A ;
TEJADA, J ;
XIN, Y ;
WONG, KW .
PHYSICA C, 1994, 232 (1-2) :99-103
[18]   MATRIX-MEDIATED SYNTHESIS OF NANOCRYSTALLINE GAMMA-FE2O3 - A NEW OPTICALLY TRANSPARENT MAGNETIC MATERIAL [J].
ZIOLO, RF ;
GIANNELIS, EP ;
WEINSTEIN, BA ;
OHORO, MP ;
GANGULY, BN ;
MEHROTRA, V ;
RUSSELL, MW ;
HUFFMAN, DR .
SCIENCE, 1992, 257 (5067) :219-223
[19]  
ZIOLO RF, UNPUB