首页> 外文期刊>Nature >Pairing of charge-ordered stripes in (La,Ca)MnO_3
【24h】

Pairing of charge-ordered stripes in (La,Ca)MnO_3

机译:(La,Ca)MnO_3中电荷有序条纹的配对

获取原文
获取原文并翻译 | 示例
           

摘要

The propensity of systems of charge and spin to form, under . certain conditions, 'stripe' phases has recently attracted much attention, as it has been suggested that dynamically fluctuating stripe phases may be of central importance for an understanding of the physics of high-temperature superconductors. A related phenomenon—static charge stripes—characterizes the insulating antiferromagnetic ground state of the manganese oxides, a class of materials which (like the copper oxide superconductors) have a perovskite structure, and are notable for their extraordinary electronic and magnetic properties, such as colossal magnetore-sistance and charge ordering. Here we report a different pattern of charge localization in the charge-ordered phase of the manganese oxide La_(1-x)Ca_xMnO_3 (x ≥ 0.5). This pattern takes the form of extremely stable pairs of Mn~(3+)O_6 stripes, with associated large lattice contractions (due to the Jahn-Teller effect), separated periodically by stripes of non-distorted Mn~(4+)O_6 octahedra. These periodicities, which adopt integer values between 2 and 5 times the lattice parameter of the orthorhombic unit cell, correspond to the commensurate carrier concentrations (x = 1/2, 2/3, 3/4 and 4/5): for other values of x, the pattern of charge ordering is a mixture of the two adjacent commensurate configurations. These paired Jahn-Teller stripes appear therefore to be the fundamental building blocks of the charge-ordered state in the manganese oxides, and so may be expected to have profound implications for the magnetic and transport properties of these materials.
机译:在的作用下,电荷和自旋形成系统的倾向。在某些情况下,“条状”相最近引起了很多关注,因为有人提出,动态波动的条带相对于理解高温超导体的物理特性可能至关重要。一种相关的现象-静电荷条纹-表征了锰氧化物的绝缘反铁磁基态。一类材料(如氧化铜超导体)具有钙钛矿结构,并因其非凡的电子和磁性而著称,例如磁阻和电荷排序。在这里,我们报告了锰氧化物La_(1-x)Ca_xMnO_3(x≥0.5)的电荷有序相中的电荷局域化的不同模式。该模式采用极其稳定的Mn〜(3+)O_6条带对的形式,并伴随着较大的晶格收缩(由于Jahn-Teller效应),周期性地被不变形的Mn〜(4+)O_6八面体条带隔开。这些周期采用正交晶胞晶格参数2到5倍的整数值,对应于相应的载流子浓度(x = 1 / 2、2 / 3、3 / 4和4/5):对于其他值在x的情况下,电荷排序的模式是两个相邻相应配置的混合。因此,这些成对的Jahn-Teller条纹似乎是锰氧化物中电荷有序状态的基本构建基块,因此可以预期会对这些材料的磁性和传输性能产生深远的影响。

著录项

  • 来源
    《Nature》 |1998年第6675期|p.473-476|共4页
  • 作者单位
  • 收录信息 美国《科学引文索引》(SCI);美国《工程索引》(EI);美国《生物学医学文摘》(MEDLINE);美国《化学文摘》(CA);
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 自然科学总论;
  • 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