SPP 1538: Spin Caloric Transport (SpinCaT)

SPP 1538：自旋热量传输 (SpinCaT)

• 批准号: 172432838
• 金额: --
• 依托单位: Arbeitsgruppe Experimentalphysik funktionaler Spinsysteme
• 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 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/172432838?language=en
• 关键词: SPP; 1538; Spin; Caloric; Transport

Spin polarised currents in magnetic nanostructures give rise to novel spin caloric effects. These effects modify thermal transport, magneto-resistance and possibly even magnetic states. To understand the observed effects an extension of thermodynamic laws including the spin is inevitable. It is long known that heat and charge currents are closely linked to each other by, e.g., the Wiedemann-Franz law, which connects thermal and electrical conductivities. The coupling leads to thermoelectric effects with prominent examples being the Seebeck effect and its inverse, the Peltier effect, which may be described through the Onsager relations. These effects are used in devices such as thermocouples and thermo-electric cooling devices, respectively. It became clear only recently that these long-known thermoelectric phenomena need to be reconsidered by including the spin. This avenue is expected to generate completely new spin-related properties in the solid state. The hypothesis that in magnetic systems spin entropy can be created, manipulated and transported by non-equilibrium charge and heat currents is compelling. Non-equilibrium magneto-caloric transport effects such as the Nernst-Ettingshausen effects will face novel spin and anomalous counterparts. Spin transport phenomena in the presence of a thermal gradient or the lateral transport of heat via magnetic excitations need to be studied.

磁性纳米结构中的自旋极化电流引起了新的自旋热效应。这些效应改变了热输运、磁阻，甚至可能改变了磁态。为了理解观察到的效应，包括自旋在内的热力学定律的扩展是不可避免的。人们早就知道，热流和电荷流是紧密联系在一起的，例如，Wiedemann-Franz定律，它将导热性和导电性联系在一起。耦合导致热电效应，突出的例子是塞贝克效应和它的逆，珀尔帖效应，这可以通过Onsager关系来描述。这些效应分别用于热电偶和热电冷却装置等设备。直到最近才清楚，这些早就知道的热电现象需要重新考虑，包括自旋。这一途径有望在固态中产生全新的自旋相关特性。在磁系统中，自旋熵可以由非平衡电荷和热流产生、操纵和传输的假设是令人信服的。非平衡磁热输运效应，如能斯特-埃廷斯豪森效应，将面临新的自旋和异常对应。存在热梯度时的自旋输运现象或通过磁激发的热的横向输运需要研究。