Influence of Fe segregation at grain boundaries on the magnetoresistance of Sr2Fe1+δMoO6 polycrystals

被引:21
作者
Kumar, Nitu [1 ,2 ]
Pandey, Vibhav [1 ]
Gaur, Anurag [2 ]
Kotnala, R. K. [1 ]
机构
[1] Natl Phys Lab, New Delhi 110012, India
[2] Natl Inst Technol, Dept Phys, Kurukshetra 136119, Haryana, India
关键词
DOUBLE-PEROVSKITE SR2FEMOO6; MAGNETIC-PROPERTIES; SITE DISORDER; TUNNELING MAGNETORESISTANCE; MAGNETOTRANSPORT PROPERTIES; TRANSPORT; ORDER; OXIDE;
D O I
10.1063/1.4757026
中图分类号
O59 [应用物理学];
学科分类号
摘要
In this paper, we report the influence of Fe impurities on the magnetoresistance (MR) of double perovskite Sr2Fe1+delta MoO6 (0.00 <= delta <= 0.20) system. The significant Fe impurities have been created by two different approaches: one by adding the extra amount of Fe2O3 at starting of the synthesis and other by sintering the pristine Sr2FeMoO6 sample at high temperature (1300 degrees C) in high reducing environment (similar to 8% H-2 + 92% Ar). A remarkable 11% magnetoresistance at room temperature under the presence of low magnetic field (0.72 T) has been observed in the pristine sample. The achieved high low field magnetoresistance value in the sample may be due to the optimized synthesis conditions to get better inter-granular tunneling through grain boundaries. However, the presence of Fe impurity results into the sharp reduction in magnetoresistance because of reduced spin polarized tunneling. The loss of insulating nature of the grain boundaries and the inelastic scattering of the charge carriers through the metallic impurities of iron at grain boundaries may be the reason of reduced spin polarized tunneling. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4757026]
引用
收藏
页数:6
相关论文
共 42 条
[1]   ESR of double-perovskite Sr2FeMoO6 [J].
Causa, MT ;
Butera, A ;
Tovar, M ;
Folatcuberta, J .
PHYSICA B-CONDENSED MATTER, 2002, 320 (1-4) :79-82
[2]   Conduction channels and magnetoresistance in polycrystalline manganites [J].
de Andrés, A ;
García-Hernández, M ;
Martínez, JL .
PHYSICAL REVIEW B, 1999, 60 (10) :7328-7334
[3]   Creep behavior and microstructure evolution of directionally solidified superalloy IC10 at high temperature [J].
School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100083, China ;
不详 .
Trans Nonferrous Met Soc China, 2006, SUPPL. 2 (122-126)
[4]   Finding universal correlations between cationic disorder and low field magnetoresistance in FeMo double perovskite series [J].
Garcia-Hernández, M ;
Martínez, JL ;
Martínez-Lope, MJ ;
Casais, MT ;
Alonso, JA .
PHYSICAL REVIEW LETTERS, 2001, 86 (11) :2443-2446
[5]   Enhanced magnetoresistance in double perovskite Sr2FeMoO4 through SrMoO4 tunneling barriers [J].
Gaur, Anurag ;
Varma, G. D. .
MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY, 2007, 143 (1-3) :64-69
[6]   Competition between intragranular and intergranular tunneling magnetoresistance in polycrystalline Sr2FeMoO6 [J].
Huang, Yun-Hui ;
Yamauchi, Hisao ;
Karppinen, Maarit .
PHYSICAL REVIEW B, 2006, 74 (17)
[7]   Spin-valve-type magnetoresistance: a generic feature of ferromagnetic double perovskites [J].
Jana, Somnath ;
Middey, Srimanta ;
Ray, Sugata .
JOURNAL OF PHYSICS-CONDENSED MATTER, 2010, 22 (34)
[8]   Magnetoresistance in doped magnetic tunnel junctions: Effect of spin scattering and impurity-assisted transport [J].
Jansen, R ;
Moodera, JS .
PHYSICAL REVIEW B, 2000, 61 (13) :9047-9050
[9]   Intergrain tunneling magnetoresistance in polycrystals of the ordered double perovskite Sr2FeReO6 [J].
Kobayashi, KI ;
Kimura, T ;
Tomioka, Y ;
Sawada, H ;
Terakura, K ;
Tokura, Y .
PHYSICAL REVIEW B, 1999, 59 (17) :11159-11162
[10]   Room-temperature magnetoresistance in an oxide material with an ordered double-perovskite structure [J].
Kobayashi, KL ;
Kimura, T ;
Sawada, H ;
Terakura, K ;
Tokura, Y .
NATURE, 1998, 395 (6703) :677-680