ANTIFERROMAGNETISM AND METALLIC CONDUCTIVITY IN NB12O29

被引:48
作者
CAVA, RJ [1 ]
BATLOGG, B [1 ]
KRAJEWSKI, JJ [1 ]
GAMMEL, P [1 ]
POULSEN, HF [1 ]
PECK, WF [1 ]
RUPP, LW [1 ]
机构
[1] RISO NATL LAB,DEPT PHYS,DK-4000 ROSKILDE,DENMARK
关键词
D O I
10.1038/350598a0
中图分类号
O [数理科学和化学]; P [天文学、地球科学]; Q [生物科学]; N [自然科学总论];
学科分类号
07 ; 0710 ; 09 ;
摘要
AT the heart of the controversy about the microscopic origin of superconductivity in high-transition-temperature copper oxide superconductors is the question of whether or not the antiferromagnetism associated with the single-hole Cu2+ 3d9 state is of fundamental importance. To test whether this unconventional spin-mediated superconductivity might be electron/hole symmetric, oxides of the elements with single d-orbital electrons, such as Ti3+ (3d1), Nb4+ (4d1) and W5+ (5d1), are of particular interest. Localized magnetic spin states and magnetic ordering have never been observed previously in transition-metal oxides with one or two electrons in the 4d or 5d states, because of the preference for conventional d-band metallic conductivity or for metal-metal bonding. In exploring the possibility of a d1-d9 and ferroelectricity-superconductivity relationship in oxides (see, for instance, ref. 1), we have found that Nb12O29, a material with a 'crystallographic shear' structure, displays simultaneously both metallic conductivity, a signature of delocalized electrons, and local-moment magnetism with an antiferromagnetic ordering temperature of 12 K. This suggests that the bonding to oxygen of the 4d levels of early-transition-metal elements may not be sufficiently covalent to yield the kind of exotic conductivity (and thus exotic superconductivity) observed for copper oxides.
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页码:598 / 600
页数:3
相关论文
共 12 条
[11]  
Wadsley A., 1970, PERSPECTIVES STRUCTU, V3, P1
[12]   MIXED OXIDES OF TITANIUM AUD NIOBIUM .1. [J].
WADSLEY, AD .
ACTA CRYSTALLOGRAPHICA, 1961, 14 (06) :660-&