DOMAIN GROWTH IN THE 3-DIMENSIONAL RANDOM-FIELD ISING MAGNET FE0.5ZN0.5F2

被引:15
作者
FENG, Q [1 ]
BIRGENEAU, RJ [1 ]
HILL, JP [1 ]
机构
[1] BROOKHAVEN NATL LAB, DEPT PHYS, UPTON, NY 11973 USA
关键词
D O I
10.1103/PhysRevB.51.15188
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Complementary neutron-scattering and superconducting quantum interference device (SQUID) magnetometry measurements have been carried out to study the time dependence of the field-cooled metastable domains in Fe0.5Zn0.5F2. These neutron-scattering data provide direct evidence of a logarithmic increase in the correlation length upon quenching the system to T≤Tc at H=5.5 T. At low temperatures the magnetic domains are frozen on experimental time scales. SQUID measurements performed at a series of fields and temperatures confirm the evolution of the excess magnetization Mex arising from domain surfaces and allow quantitative analysis of its time dependence. Specifically, we found that Mex∼HMν[ln(t/τ)]-ψ, where νM=2.7±0.1 and ψ=1.1±0.3 for H3.45 T; ψ is much less than 1 for lower fields. In particular, ψ=0.42±0.14 at H=1.5 T, in agreement with a prediction by Nattermann and Vilfan. At H=5.5 T, Mex(T) and the inverse correlation length κ(T) exhibit identical time dependences. Overall, these measurements reveal the varied time dependence of a field-cooled, strongly anisotropic dilute antiferromagnet in different applied fields, and shed light on the mechanisms of domain evolution. © 1995 The American Physical Society.
引用
收藏
页码:15188 / 15196
页数:9
相关论文
共 37 条
[21]  
Nattermann T., Vilfan I., Phys. Rev. Lett., 61, (1988)
[22]  
Lederman M., Selinger J.V., Bruinsma R., Orbach R., Hammann J., Phys. Rev. B, 48, (1993)
[23]  
Feng Q., Harris Q.J., Birgeneau R.J.
[24]  
Hill J.P., Feng Q., Birgeneau R.J., Thurston T.R., Phys. Rev. Lett., 70, (1993)
[25]  
Birgeneau R.J., Feng Q., Harris Q.J., Hill J.P., Ramirez A.P., Thurston T.R.
[26]  
Yoshizawa H., Cowley R.A., Shirane G., Birgeneau R.J., Phys. Rev. B, 31, (1985)
[27]  
Nowak U., Usadel K.D., Phys. Rev. B, 46, (1992)
[28]  
Fundamentals of Crystallography, (1992)
[29]  
Prejean J.J., Souletie J., J. Phys. (Paris), 41, (1980)
[30]  
Hutchings M.T., Rainford B.D., Guggenheim H.J., J. Phys. C, 3, (1970)