Neutron studies of the iron-based family of high T-C magnetic superconductors

	Neutron studies of the iron-based family of high T-C magnetic superconductors
	Lynn, JW ; Dai, PC
刊名	PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS
	2009
卷号	469 期号:9-12 页码:469
关键词	SCATTERING
ISSN号	0921-4534
通讯作者	Lynn, JW (reprint author), Natl Inst Stand & Technol, Ctr Neutron Res, Gaithersburg, MD 20899 USA.
中文摘要	We review neutron scattering investigations of the crystal structures, magnetic structures, and spin dynamics of the iron-based RFe(As, P)(O, F) (R = La, Ce. Pr, Nd), (Ba,Sr,Ca)Fe2As2, and Fe1+x(Te-Se) systems. On cooling from room temperature all the undoped materials exhibit universal behavior, where a tetragonal-to-orthorhombic/monoclinic structural transition Occurs, below which the systems become antiferromagnets. For the first two classes of materials the magnetic structure within the a-b plane consists of chains of parallel Fe spins that are coupled antiferromagnetically in the orthogonal direction, with an ordered moment typically less than one Bohr magneton. Hence these are itinerant electron magnets, with a spin structure that is consistent with Fermi-surface nesting and a very energetic spin wave bandwidth similar to 0.2 eV. With doping, the structural and magnetic transitions are suppressed in favor of superconductivity, with Superconducting transition temperatures up to approximate to 55 K. Magnetic correlations are observed in the Superconducting regime, With a Magnetic resonance that follows the Superconducting order parameter just like the cuprates. The rare earth moments order antiferromagnetically at low T like 'conventional' Magnetic Superconductors, while the Cc crystal field linewidths are affected when superconductivity sets in. The application of pressure in CaFe2As2 transforms the system from a magnetically ordered orthorhombic material to a 'collapsed' non-magnetic tetragonal system. Tetragonal Fe1+xTe transforms to a low T monoclinic structure at small x that changes to orthorhombic at larger x, which is accompanied by a crossover from commensurate to incommensurate magnetic order. Se doping Suppresses the magnetic order, while incommensurate magnetic correlations are observed in the superconducting regime. (C) 2009 Elsevier B.V. All rights reserved.
收录类别	SCI
资助信息	US Department of Energy, Division of Materials Science, Basic Energy Sciences [DE-FG02-05ER46202]; US National Science Foundation [DMR-0756568]
语种	英语
公开日期	2014-02-20
内容类型	期刊论文
源URL	[http://ir.iphy.ac.cn/handle/311004/57841]
专题	物理研究所_所内人员在其他单位发表论文题录信息_所内人员在其他单位发表论文题录信息_期刊论文
推荐引用方式 GB/T 7714	Lynn, JW,Dai, PC. Neutron studies of the iron-based family of high T-C magnetic superconductors[J]. PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS,2009,469(9-12):469.
APA	Lynn, JW,&Dai, PC.(2009).Neutron studies of the iron-based family of high T-C magnetic superconductors.PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS,469(9-12),469.
MLA	Lynn, JW,et al."Neutron studies of the iron-based family of high T-C magnetic superconductors".PHYSICA C-SUPERCONDUCTIVITY AND ITS APPLICATIONS 469.9-12(2009):469.