Strongly enhanced tunneling magnetoresistance in granular films of Co clusters in a CO2 matrix:: Evidence for a cluster-surface/matrix interaction

被引：9

作者：

Zare-Kolsaraki, H ^{[1
]}

Hackenbroich, B ^{[1
]}

Micklitz, H ^{[1
]}

机构：

[1] Univ Cologne, Inst Phys 2, D-50937 Cologne, Germany

来源：

EUROPHYSICS LETTERS | 2002年 / 57卷 / 06期

关键词：

D O I：

10.1209/epl/i2002-00590-3

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

A new granular system, namely, Co clusters embedded in solid CO (2), has been prepared by the co-deposition of well-defined Co clusters (mean diameter L similar or equal to 4.2 nm, and CO2 molecules onto a cold substrate. This system shows a temperature-dependent tunneling magnetoresistance (TMR) which has a value of 31(2)% at 2.5 K. Using Julliere's model this value corresponds to a spin-polarisation |P| = 0.68(2) of the tunneling electrons, compared to P = 0.42 for granular Co/Xe(Kr) or planar Co/Al2O3/Co. We interpret this enhancement of P as caused by a cluster-surface/matrix interaction.

引用

页码：866 / 871

页数：6

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