...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Physical review >Strong magnetic correlations to 900 K in single crystals of the trigonal antiferromagnetic insulators SrMn_2As_2 and CaMn_2As_2
【24h】

Strong magnetic correlations to 900 K in single crystals of the trigonal antiferromagnetic insulators SrMn_2As_2 and CaMn_2As_2

机译：三角反铁磁绝缘子SrMn_2As_2和CaMn_2As_2的单晶中与900 K的强磁性相关

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Crystallographic, electronic transport, thermal, and magnetic properties are reported for SrMn_2As_2 and CaMn_2As_2 single crystals grown using Sn flux. Rietveld refinements of powder x-ray diffraction data show that the two compounds are isostructural and crystallize in the trigonal CaAl_2Si_2-type structure (space group P3m1), in agreement with the literature. Electrical resistivity ρ versus temperature T measurements demonstrate insulating ground states for both compounds with activation energies of 85 meV for SrMn_2As_2 and 61 meV for CaMn_2As_2. In a local-moment picture, the Mn~(+2) 3d~5 ions are expected to have high-spin S = 5/2 with spectroscopic splitting factor g ≈ 2. Magnetic susceptibility X and heat capacity C_p measurements versus T reveal antiferromagnetic (AFM) transitions at T_N = 120(2) K and 62(3) K for SrMn_2As_2 and CaMn_2As_2, respectively. The anisotropic X(T ≤ _N) data indicate that the hexagonal c axis is the hard axis and hence that the ordered Mn moments are aligned in the ab plane. The X(T) data for both compounds and the C_p(T) for SrMn_2As_2 show strong dynamic short-range AFM correlations from _N up to at least 900 K, likely associated with quasi-two-dimensional connectivity of strong AFM exchange interactions between the Mn spins within the corrugated honeycomb Mn layers parallel to the ab plane.
机译：报告了使用Sn助熔剂生长的SrMn_2As_2和CaMn_2As_2单晶的晶体学，电子传输，热和磁性能。粉末X射线衍射数据的Rietveld精炼表明，这两种化合物在三角形CaAl_2Si_2型结构（空间群P3m1）中是同构的且结晶的，与文献一致。电阻率ρ与温度T的测量结果表明，两种化合物的绝缘基态均具有SrMn_2As_2的活化能为85 meV，CaMn_2As_2的活化能为61 meV。在局部时刻的图片中，Mn〜（+2）3d〜5离子具有高自旋S = 5/2，并且具有光谱分裂因子g≈2。对于SrMn_2As_2和CaMn_2As_2，（AFM）跃迁分别在T_N = 120（2）K和62（3）K处发生。各向异性X（T≤_N）数据表明六边形c轴是硬轴，因此有序Mn矩在ab平面中对齐。两种化合物的X（T）数据和SrMn_2As_2的C_p（T）数据均显示从_N到至少900 K的强动态短程AFM相关性，可能与强AFM交换相互作用之间的准二维连通性有关。锰在波纹蜂窝状锰层中平行于ab平面旋转。

著录项

  • 来源
    《Physical review》 |2016年第9期|094417.1-094417.10|共10页
  • 作者

    N. S. Sangeetha; Abhishek Pandey; Zackery A. Benson; D. C. Johnston;

  • 作者单位

    Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA;

    Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA,Department of Physics and Astronomy, Texas A&M University, College Station, Texas 77840-4242, USA;

    Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA;

    Ames Laboratory and Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA;

  • 收录信息
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号