Verduci Tindara, Chaumy Guillaume, Dayen Jean-Francois, Leclerc Nicolas, Devaux Eloïse, Stoeckel Marc-Antoine, Orgiu Emanuele, Samorì Paolo, Doudin Bernard
University of Strasbourg, CNRS, IPCMS UMR 7504, 23 rue du Loess, F-67034 Strasbourg, France.
Nanotechnology. 2018 Sep 7;29(36):365201. doi: 10.1088/1361-6528/aacc22. Epub 2018 Jun 12.
The predominance of interface resistance makes current crowding ubiquitous in short channel organic electronics devices but its impact on spin transport has never been considered. We investigate electrochemically doped nanoscale PBTTT short channel devices and observe the smallest reported values of crowding lengths, found for sub-100 nm electrodes separation. These observed values are nevertheless exceeding the spin diffusion lengths reported in the literature. We discuss here how current crowding can be taken into account in the framework of the Fert-Jaffrès model of spin current propagation in heterostructures, and predict that the anticipated resulting values of magnetoresistance can be significantly reduced. Current crowding therefore impacts spin transport applications and interpretation of the results on spin valve devices.
界面电阻的主导作用使得电流拥挤现象在短沟道有机电子器件中普遍存在，但其对自旋输运的影响从未被考虑过。我们研究了电化学掺杂的纳米级PBTTT短沟道器件，并观察到在电极间距小于100 nm时出现了迄今报道的最小拥挤长度值。然而，这些观测值仍超过了文献中报道的自旋扩散长度。我们在此讨论如何在异质结构中自旋电流传播的费特 - 雅夫雷斯模型框架内考虑电流拥挤，并预测预期的磁阻结果值会显著降低。因此，电流拥挤会影响自旋输运应用以及自旋阀器件结果的解释。
