Single Molecule Electronic Transport through Molecular Magnets

通过分子磁体的单分子电子传输

• 批准号: 5369165
• 负责人: Professor Dr. Herbert Schoeller
• 金额: --
• 依托单位: Institut für Theorie der Statistischen Physik
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2002
• 资助国家: 德国
• 起止时间: 2001-12-31 至 2004-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/5369165?language=en
• 关键词: Single; Molecule; Electronic; Transport; through

Electrical and magnetic devices based on single molecules offer exciting perspectives for the further minituarization of electronic devices with a potentially large impact in applications. To date several experiments have shown the possibility to attach individual molecules to leads and to measure the electrical transport. With recent technological improvements in the design of single-molecule magnets (SMM), experiments and devices that combine spin- and molecular electronics become realistic. Transport through SMM offers several unique features that have not been exploited to date: - SMM couple naturally to applied external magnetic fields and may thus function as magnetic sensors, switches or storage devices. - In the limit of weak coupling between electrodes and SMM a strong interaction between transport effects and magnetic structure can lead to interesting physical effects, such as current assisted spin-tunneling, spin fluctuations leading to Kondo effects, magneto-Coulomb-oscillations, and spin-accumulation. - In contrast to organic systems, the molecular orbitals which carry the current and which are responsible for the magnetic properties of the system are spatially confined, i.e. they are less susceptible to the influence of the external electric field. In this investigation we plan to develop microscopic models to calculate the electronic two-terminal transport though a molecular magnet in the presence of an applied magnetic and electric field and to determine the transport characteristics through such a system for weak coupling between electrode and SMM, where strong Coulomb correlations and many-body effects are important.

基于单分子的电磁器件为电子器件的进一步小型化提供了令人兴奋的前景，在应用中具有潜在的巨大影响。到目前为止，几个实验已经显示了将单个分子连接到引线上并测量电传输的可能性。随着单分子磁体（SMM）设计的最新技术进步，结合自旋和分子电子学的实验和设备变得现实。通过SMM传输提供了几个迄今为止尚未开发的独特功能：- SMM与施加的外部磁场自然耦合，因此可以用作磁传感器，开关或存储设备。-在电极和SMM之间弱耦合的极限下，输运效应和磁性结构之间的强相互作用可以导致有趣的物理效应，例如电流辅助自旋隧穿，导致近田效应的自旋涨落，磁库仑振荡和自旋积累。-与有机系统相比，携带电流和负责系统磁性的分子轨道在空间上是受限的，即它们不易受外电场的影响。在这项研究中，我们计划开发微观模型来计算在外加磁场和电场存在下通过分子磁铁的电子两端输运，并确定通过这种电极和SMM之间弱耦合系统的输运特性，其中强库仑相关和多体效应是重要的。