Effect of pinholes in magnetic tunnel junctions

被引:14
作者
Chen, Xi [1 ]
Victora, R. H.
机构
[1] Univ Minnesota, Sch Phys & Astron, Minneapolis, MN 55455 USA
[2] Univ Minnesota, Dept Elect & Comp Engn, Minneapolis, MN 55455 USA
基金
美国国家科学基金会;
关键词
D O I
10.1063/1.2814038
中图分类号
O59 [应用物理学];
学科分类号
摘要
The electron transport in magnetic tunnel junction containing pinholes is studied, where ferromagnetic layers make direct contact through narrow conducting channels. The transport is treated within the Landauer formalism using a tight-binding Hamiltonian. It is found that a narrow pinhole induces a resonant tunneling behavior causing a magnetoresistance that oscillates with the bias voltage. After averaging over pinholes of various shapes, the oscillation and magnitude of magnetoresistance (MR) are reduced, which can explain how barrier roughness diminishes the MR. For a pinhole of a large radius, where the number of atoms inside is much larger than 1, an enhanced MR is obtained whose value is similar to an all-metal giant magnetoresistance spin valve. (C) 2007 American Institute of Physics.
引用
收藏
页数:3
相关论文
共 25 条
[1]   Geometrically constrained magnetic wall [J].
Bruno, P .
PHYSICAL REVIEW LETTERS, 1999, 83 (12) :2425-2428
[2]  
Costa V. D., 2000, PHYS REV LETT, V85, P876
[3]  
DATTA S, 1997, ELECT TRANSPORT MESO, pCH3
[4]   Magnetic tunneling applied to memory [J].
Daughton, JM .
JOURNAL OF APPLIED PHYSICS, 1997, 81 (08) :3758-3763
[5]   Local investigation of thin insulating barriers incorporated in magnetic tunnel junctions [J].
Dimopoulos, T ;
Da Costa, V ;
Tiusan, C ;
Ounadjela, K ;
van den Berg, HAM .
JOURNAL OF APPLIED PHYSICS, 2001, 89 (11) :7371-7373
[6]  
FERRY DK, 1997, TRANSPORT NANOSTRUCT, pCH3
[7]   RELATION BETWEEN CONDUCTIVITY AND TRANSMISSION MATRIX [J].
FISHER, DS ;
LEE, PA .
PHYSICAL REVIEW B, 1981, 23 (12) :6851-6854
[8]   CPP-GMR films with a current-confined-path nano-oxide layer (CCP-NOL) [J].
Fukuzawa, Hideaki ;
Yuasa, Hiromi ;
Iwasaki, Hitoshi .
JOURNAL OF PHYSICS D-APPLIED PHYSICS, 2007, 40 (05) :1213-1220
[9]   Microstructured magnetic tunnel junctions [J].
Gallagher, WJ ;
Parkin, SSP ;
Lu, Y ;
Bian, XP ;
Marley, A ;
Roche, KP ;
Altman, RA ;
Rishton, SA ;
Jahnes, C ;
Shaw, TM ;
Xiao, G .
JOURNAL OF APPLIED PHYSICS, 1997, 81 (08) :3741-3746
[10]   Negative and positive magnetoresistance manipulation in an electrodeposited nanometer Ni contact [J].
García, N ;
Rohrer, H ;
Saveliev, IG ;
Zhao, YW .
PHYSICAL REVIEW LETTERS, 2000, 85 (14) :3053-3056