中文

Mg 掺杂 CuGeO_3 成分相变的临界中子散射研究

强关联电子 2009-10-31 v4 材料科学

摘要

Cu_{1-x}Mg_xGeO_3 在临界浓度 xcx_c 处经历一级相变,从二聚化晶格上的反铁磁态(D-AF)转变为未畸变均匀晶格上的反铁磁内尔态(U-AF)。先前的磁化率测量给出 xc=0.023x_c = 0.023,而最近的中子散射研究报道 xc=0.027±0.001x_c = 0.027 \pm 0.001。本工作中,由超晶格反射 (0,1,1/2)(0,1,1/2) 附近的反铁磁涨落引起的临界散射明确地确定了 xc=0.028±0.001x_c = 0.028 \pm 0.001TN=3.44T_N = 3.4 \sim 4 K)。此外,在 T=1.3T = 1.3 K 时,通过观测跨越 xcx_c 的有效磁矩跳变,确定了相边界 xc=0.028±0.001x_c = 0.028 \pm 0.001

关键词

引用

@article{arxiv.cond-mat/0002429,
  title  = {Critical neutron scattering study of the compositional phase transition in Mg-doped CuGeO3},
  author = {M. Nishi and H. Nakao and Y. Fujii and T. Masuda and K. Uchinokura and G. Shirane},
  journal= {arXiv preprint arXiv:cond-mat/0002429},
  year   = {2009}
}

备注

8 pages,3 figures, Post Scripts, PACS numbers: 75.30.Kz, 75.40.-s, 61.12, 75.30.K. submitted to Journal of Physical Society of Japan