Large magneto-Seebeck effect in magnetic tunnel junctions with half-metallic Heusler electrodes

被引：52

作者：

Boehnke, Alexander ^{[1
]}

Martens, Ulrike ^{[2
]}

Sterwerf, Christian ^{[1
]}

Niesen, Alessia ^{[1
]}

Huebner, Torsten ^{[1
]}

von der Ehe, Marvin ^{[2
]}

Meinert, Markus ^{[1
]}

Kuschel, Timo ^{[1
,3
]}

Thomas, Andy ^{[4
]}

Heiliger, Christian ^{[5
]}

Muenzenberg, Markus ^{[2
]}

Reiss, Guenter ^{[1
]}

机构：

[1] Bielefeld Univ, Phys Dept, Ctr Spinelect Mat & Devices, Univ Str 25, D-33615 Bielefeld, Germany

[2] Ernst Moritz Arndt Univ Greifswald, Inst Phys, Felix Hausdorff Str 6, D-17489 Greifswald, Germany

[3] Univ Groningen, Zernike Inst Adv Mat, Phys Nanodevices, Nijenborgh 4, NL-9747 AG Groningen, Netherlands

[4] Inst Metall Mat, Leibniz Inst Solid State & Mat Res Dresden IFW Dr, Helmholtzstr 20, D-01069 Dresden, Germany

[5] Justus Liebig Univ Giessen, Inst Theoret Phys, Heinrich Buff Ring 16, D-35392 Giessen, Germany

来源：

NATURE COMMUNICATIONS | 2017年 / 8卷

关键词：

THERMAL-CONDUCTIVITY; SPIN CALORITRONICS; AB-INITIO; CONDUCTANCE; TORQUES; SILICON; FILMS;

D O I：

10.1038/s41467-017-01784-x

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：

Spin caloritronics studies the interplay between charge-, heat- and spin-currents, which are initiated by temperature gradients in magnetic nanostructures. A plethora of new phenomena has been discovered that promises, e.g., to make wasted heat in electronic devices useable or to provide new read-out mechanisms for information. However, only few materials have been studied so far with Seebeck voltages of only some microvolt, which hampers applications. Here, we demonstrate that half-metallic Heusler compounds are hot candidates for enhancing spin-dependent thermoelectric effects. This becomes evident when considering the asymmetry of the spin-split density of electronic states around the Fermi level that determines the spin-dependent thermoelectric transport in magnetic tunnel junctions. We identify Co2FeAl and Co2FeSi Heusler compounds as ideal due to their energy gaps in the minority density of states, and demonstrate devices with substantially larger Seebeck voltages and tunnel magneto-Seebeck effect ratios than the commonly used Co-Fe-B-based junctions.

引用

页数：7