Unprecedented magnetoresistance in Cd-substituted Tl2Mn2O7 pyrochlores

被引：22

作者：

Alonso, JA ^{[1
]}

Velasco, P

Martínez-Lope, MJ

Casais, MT

Martínez, JL

Fernández-Díaz, MT

de Paoli, JM

机构：

[1] CSIC, Inst Ciencia Mat, E-28049 Madrid, Spain

[2] Inst Max Von Laue Paul Langevin, F-38042 Grenoble 9, France

[3] Univ Nacl Cordoba, Fac Ciencias Quim, Dept Fisicoquim, RA-5000 Cordoba, Argentina

来源：

APPLIED PHYSICS LETTERS | 2000年 / 76卷 / 22期

关键词：

D O I：

10.1063/1.126604

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Moderate pressure techniques (P=20 kbar) have been used to prepare Tl2-xCdxMn2O7 (0 less than or equal to x less than or equal to 0.4) pyrochlore-like materials. The x=0.2 compound has been characterized by neutron powder diffraction, magnetic, magnetotransport, and Hall measurements. This material is ferromagnetic below T-C=110 K. Both electrical resistance and magnetoresistance (MR) are enhanced with respect to stoichiometric Tl2Mn2O7, due to the drastic reduction in the number of carriers (electrons) induced by hole doping. MR(0.5 T) is higher than 10(6)% at 120 K, and MR(9 T) is 30% at room temperature. We show that hole doped derivatives of Tl2Mn2O7 are promising candidates in which to search for large bulk magnetoresistance. (C) 2000 American Institute of Physics. [S0003-6951(00)00822-6].

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页码：3274 / 3276

页数：3

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