Spin-current-induced modification of the thermal Boltzmann distribution in paramagnetic and ferromagnetic nanostructures

自旋电流诱导顺磁和铁磁纳米结构中热玻尔兹曼分布的修改

• 批准号: 198555588
• 负责人: Dr. Ralf Meckenstock
• 金额: --
• 依托单位: Institut für Halbleiter- und Festkörperphysik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2011
• 资助国家: 德国
• 起止时间: 2010-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/198555588?language=en
• 关键词: Spin; current; induced; modification; thermal

It has been recently demonstrated that spin-polarized currents which flow through magnetic nano-devices result in an effective cooling of the spin system. Such direct effects of spin-polarized currents, like the spin-Seebeck or Peltier effect, correlate spin currents with temperature gradients. In this project we aim at studying the cooling of paramagnetic systems induced by spin-polarized currents. Microwave irradiation under electron spin resonance (ESR) conditions will be used to saturate the spin-up and spindown states in a paramagnet grown on a ferromagnetic spin injector. The spinpolarized currents are expected to change the balance of the different spin-states resulting in an effective cooling indicated by the appearance of the ESR signal. The ESR will be detected by microwave absorption and thermal response of the system, providing a measure for the absorption to emission ratio. Such systems can be considered as prototype devices for spin current induced cooling of quantum dot systems and microwave- controlled spintronic devices. The latter bears the potential to be operational using very low current densities. Another advantage of the proposed method is the potential to fully characterize the magnetic high-frequency susceptibility and anisotropy of the ferromagnetic electrodes, which are used as spin polarisers. A full set of static and dynamic magnetic parameters of all magnetically active constituents, including the temperature dependence, element specificity via specific transitions and in-situ measurements during growth will be experimentally determined.

最近已经证明，流过磁性纳米器件的自旋极化电流导致自旋系统的有效冷却。自旋极化电流的这种直接效应，如自旋塞贝克效应或珀尔帖效应，将自旋电流与温度梯度相关联。在这个项目中，我们的目的是研究自旋极化电流诱导的顺磁系统的冷却。电子自旋共振（ESR）条件下的微波辐照将被用来饱和的自旋上和自旋下的状态在顺磁体上生长的铁磁自旋注入器。预计自旋极化电流将改变不同自旋状态的平衡，从而产生有效的冷却，这由ESR信号的出现指示。ESR将通过系统的微波吸收和热响应来检测，提供吸收发射比的度量。这样的系统可以被认为是用于量子点系统的自旋电流诱导冷却和微波控制的自旋电子器件的原型器件。后者具有使用非常低的电流密度进行操作的潜力。所提出的方法的另一个优点是充分表征磁高频磁化率和各向异性的铁磁电极，这是用作自旋极化器的潜力。将通过实验确定所有磁活性成分的一整套静态和动态磁参数，包括温度依赖性、通过特定转变的元素特异性和生长期间的原位测量。

项目成果

Magnetic anisotropy and relaxation of single Fe/FexOy core/shell- nanocubes: A ferromagnetic resonance investigation

单个 Fe/FexOy 核/壳纳米立方体的磁各向异性和弛豫：铁磁共振研究

• DOI: 10.1063/1.4944399
• 发表时间: 2016
• 期刊: AIP Advances
• 影响因子: 1.6
• 作者: Alexandra Terwey;Ralf Meckenstock;Benjamin Zingsem;Sabrina Masur;Christian Derricks;Florian M. Römer;Michael Farle
• 通讯作者: Michael Farle

Spin-Current Detection via an Interfacial Molecular Paramagnet

• DOI: 10.1103/physrevapplied.10.054002
• 发表时间: 2018-11
• 期刊: Physical Review Applied
• 影响因子: 4.6
• 作者: T. Marzi;R. Meckenstock;S. Masur;M. Farle