自旋交叉配合物分子自旋双稳态的可逆调控

Reversible switching of single molecular spin state is one of the hottest fields in physics, chemistry and information technology. Among several types of molecular magnets, spin crossover molecule is one of the best candidate for industrial application because its spin switching could be operated at room temperature. By using low-temperature scanning tunneling microscope (STM), we plan to investigate the magnetic properties of single crossover molecules at0.5 K and under 0-11 Tesla magnetic field. Putting spin crossover molecules on surfaces of metal substrate, copper nitride film, copper oxide film, or sodium chloride film, the adsorption and self-assembly of the molecules will be studied. The properties of the adsorbed spin crossover molecules will be investigated extensively by scanning tunneling spectroscopy (STS) . By manipulating single atoms and single molecules, we will discover the reasons which cause the quenching of magnetism of some spin crossover molecules on surfaces. By analyzing the tunneling spectra, the contribution of direct tunneling, spin-flip, and Kondo resonance to the spectra can be quantitatively determined. Following the molecular self-assembly nature, spin crossover molecules arranged themselves in ordered arrays on surfaces. On molecules in the ordered arrays, we will realize precisely controlled reversible switching of the bistable spin states of spin crossover molecules.

单分子自旋态可逆调控是目前物理、化学以及信息技术等领域的研究热点。自旋交叉配合物可以在室温出现自旋双稳态的可逆转换，最有机会实现工业应用。通过低温强磁场扫描隧道显微镜（STM），我们计划系统研究检测单个自旋交叉配合物分子在金属、氮化铜薄膜、氧化铜薄膜、氯化钠薄膜等基底上的吸附与自组装行为，制备各种有序分子阵列。通过微分电导谱，研究自旋交叉配合物在表面的自旋态，并使用针尖脉冲，调控分子自旋态。采用单原子与单分子操纵，研究自旋交叉配合物在表面上的磁性淬灭机制。并透过隧穿电流谱学，研究单个自旋交叉配合物的直接隧穿、自旋翻转以及近藤共振之间的定量关系。最终我们希望实现自旋交叉配合物有序阵列中分子自旋双稳态的逐一可逆调控。

分子自旋电子学是一门综合交叉学科，涵盖了分子磁学、分子电子学、有机自旋电子学和量子计算等领域。而对单分子自旋态进行精确检测和调控是制备分子自旋电子器件的前提基础。我们系统研究了磁性分子的自旋态，并采用单分子化学的手段实现了对其输运性质的调控。为了研究自旋耦合，我们也对磁性分子在表面的自组装进行了深入研究。 项目执行期间，共发表SCI论文21篇。重要结果包括：自旋载流子为2p, 3d或4f电子的磁性分子自旋态检测与调控；Au(111)表面真空合成磁性酞菁铝分子；表面构建谢尔宾斯基三角分形结构。