In-situ Electrochemical Fabrication of Single Molecule Spintronic Junctions

自旋电子学代表了电子学的一个新方向，因为它利用了电子的自旋以及更常见的电子电荷。自旋是一种量子力学性质，其结果可以在材料的磁性行为中看到。自旋电子器件已经投入生产，例如，用于读取磁盘信息的传感器。然而，这些和大多数其他现有的自旋电子器件都是由金属和氧化物制成的。引入新材料将创造令人兴奋的新机会，这个项目将研究如何将有机分子集成到自旋电子器件中。使用有机分子取代传统的无机导体和绝缘体的部分原因是，理论预测自旋的传输损失可能比其他材料更低，部分原因是有机化学为以有趣的方式改变分子的性质提供了许多机会。我们将制造最小的自旋电子器件，由两个由单个分子连接的磁性金属触点组成，并测量它们的磁传输特性(电流如何受到磁场的影响)。一次研究一个分子，消除了之前对分子集合研究中发现的许多不确定性，例如，分子是否真的以化学方式与金属接触结合。尽管具有挑战性，但使用扫描调谐显微镜测量通过单个分子的电流是可能的，扫描调谐显微镜是一种可以控制两个金属接触的分离的仪器，其精度小于单个原子的直径。在这个项目中，我们将通过开发使用离子液体(一种特殊类型的溶剂)的新的电化学方法来改进以前的研究。我们的新测量将比以前更快、更干净。我们希望看到一系列有趣的行为，包括我们可以通过外加电势控制的自旋传输，这将是一个相当于晶体管的分子自旋电子学。作为迈向实用自旋电子器件的一步，我们还将使用电化学和微电子工业中使用的一些技术来制造基于明确定义的有机分子单分子层的更强大的自旋电子器件。

Spintronics represents a new direction for electronics as it exploits the spin of the electron as well as the more familiar electron charge. Spin is a quantum mechanical property, and its consequences are seen in the magnetic behaviour of materials. Spintronic devices are already in production, for example, the sensor used to read information on magnetic hard disks. However, these and most other existing spintronic devices are made only of metals and oxides.Introducing new materials will create exciting new opportunities, and this project will look at how organic molecules can be integrated into spintronic devices. The reason to use organic molecules in place of conventional inorganic conductors and insulators is partly that theory predicts that spin may be transported with lower loss than in other materials and partly that organic chemistry affords many opportunities for changing the properties of molecules in interesting ways. We will make the smallest spintronic devices possible, consisting of two magnetic metal contacts joined by a single molecule and measure their magneto-transport properties (how the electric current is affected by a magnetic field). Studying one molecule at a time removes many of the uncertainties found in previous studies of collections of molecules, where it was unclear, for example, whether the molecules were really bound chemically to the metal contacts. Though challenging it is possible to measure the current thorugh a single molecule using a scanning tunelling microscope, which is an instrument that can control the separation of two metal contacts with a precision of less than the diameter of a single atom . In this project we will improve on previous studies by developing new electrochemical methods, using ionic liquids (a special type of solvent). Our new measurements will be much faster and cleaner than was possible before. We expect to see a range of interesting behaviours, including spin transport that we can control with an external potential, This will be a molecular spintronic equivalent of the transistor. As a step towards a practical spintronic device, we will also use electrochemistry together with some of the technologies used in the microelectronics industry to make a more robust spintronic device based on a well-defined monolayer of organic molecules.