Experimental evidence of magnetic training effect of electronic phase in Nd-Ca half-doped manganite

来源 :稀土学报(英文版) | 被引量 : 0次 | 上传用户:xsb
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Cooling and heating modes are shown to be able to significantly modify the magnetic and electrical properties of the half-doped perovskite manganite. The present paper reports on a precise investigation of this phenomenon (the so-called training effect) carried out on Nd0.5Ca0.5MnO3 manganite, which allow a fine tuning of the magnetic ground state. Refinement of the X-ray diffraction pattern shows that the synthesized sample is single phase and crystallizes in the orthorhombic structure with Pnma space group. Using magnetometry measurements, we have found that the sample is the seat of interesting phenomena like charge ordering, magnetic phase separation, spin-glass and inverse magnetocaloric effect. Magnetic-field-driven magnetization (M(μ0H)) measurements evidence the metamagnetic tran-sition which not only depends on field value, but also on the thermal process (cooling or heating). Metamagnetic irreversibility in the magnetic field range (±5 T) and memory effect are observed at low temperatures due to the kinetic arrest phenomenon. It is worthwhile to mention that the coercive field increases with decreasing temperature and reaches 955 Oe at 20 K, which is sufficiently large compared with that one in the soft magnetic and makes the material quite interesting for spintronic applications. The electrical resistivity in a zero field was measured on both cooling and warming modes, and the data obtained were fitted by using different theoretical models. At low temperatures, the resistivity shows the presence of insulator-metal transition and is found to be in conformity with the magnetization data. A magnetic training effect due to the thermo-magnetic history dependent behavior is observed, where the resistivity is consistently irreversible.
其他文献
现代物流管理被国内外学术界和企业界公认为是在降低物资消耗、提高劳动生产率之外的“第三利润源泉”,随着现代科学技术和全球经济一体化的发展,企业物流管理也越来越受到大型
学位
摘要:随着我国教育教学改革的不断深入与发展,对于各学科的教学要求也越来越高。在初中阶段的所有课程中,体育是一门比较重要的学科,它不仅能够使学生的体质得到一定程度的增强,对于有效锻炼学生的意志力也有一定的帮助。根据新课改的要求,初中体育教学的模式也发生了很大的变化,如何提升学生的主动参与性也成了体育教学的重点和难点。本文就关于上述内容做进一步讨论,提出几点有效策略。  关键词:初中体育;主動参与度;
Rare earths (REs) and Co are critical strategic resources. Their recovery is crucial for ensuring that their supplies are adequate and for reducing environmenta
在金融危机的大环境下,本土和外资的广告主更倾向于采用杠铃式的营销投放结构,在这种情况下,公交移动电视收视率的结果更有助于促进广告主当前的营销策略。 In the context
这些年来,我国的汽车产业渐渐进入了快速发展的时期。在这种发展趋势和形式下,国内的各个银行已经相应加大了对于汽车消费金融产品的关注与推广力度。当前,国内主要存在下面几种
现代公路交通的发展,有力的支持了我国经济建设,预防性养护工作的开展,更是为农村公路工程的建设质量提供了重要保障。本文探讨了当前农村公路采取的预防性养护措施,为进一步提高
随着教育事业的不断改革,教学条件得到了提高,教学方法也在不断完善.然而,学生的思维转换能力、创新能力的培养方面还是偏弱,有待提高.对于当代初中生来说,教师在数学课上所
随着新课改的深入和《新课程标准》的实施,高中思政课程应当反映新时代的要求,关注学生个性化、多样化的学习和发展需求,这不仅是教育行政管理部门的要求,也是高中政治学科建
自然金和银金矿是天然产出的含有金、银和少量铜的合金 ,它们最常见 ,是矿石中的金的主要产出形式。用重选、浮选或氰化法从含 0 1~ 2 0 g/tAu矿石中回收它们已工业化了。本
数学教学质量的提升主要是课堂教学模式的转变.本文围绕学案导学、互助教学、积分制评价三大教学策略,为实际数学教学提高课堂质量做了有力的论证,并收到了良好的效果.