Université de Strasbourg, CNRS, IPCMS, UMR 7504, F-67000, Strasbourg, France.
Instituto de Física de Rosario, Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Universidad Nacional de Rosario, Bv. 27 de Febrero 210bis S2000EZP, Rosario, Argentina.
Nat Commun. 2017 Dec 7;8(1):1974. doi: 10.1038/s41467-017-02151-6.
The active control of a molecular spin represents one of the main challenges in molecular spintronics. Up to now spin manipulation has been achieved through the modification of the molecular structure either by chemical doping or by external stimuli. However, the spin of a molecule adsorbed on a surface depends primarily on the interaction between its localized orbitals and the electronic states of the substrate. Here we change the effective spin of a single molecule by modifying the molecule/metal interface in a controlled way using a low-temperature scanning tunneling microscope. A nickelocene molecule reversibly switches from a spin 1 to 1/2 when varying the electrode-electrode distance from tunnel to contact regime. This switching is experimentally evidenced by inelastic and elastic spin-flip mechanisms observed in reproducible conductance measurements and understood using first principle calculations. Our work demonstrates the active control over the spin state of single molecule devices through interface manipulation.
分子自旋的主动控制是分子自旋电子学的主要挑战之一。到目前为止，自旋的操纵是通过化学掺杂或外部刺激来改变分子结构来实现的。然而，吸附在表面上的分子的自旋主要取决于其局域轨道和衬底电子态之间的相互作用。在这里，我们使用低温扫描隧道显微镜以受控的方式改变分子/金属界面，从而改变单个分子的有效自旋。当将电极-电极距离从隧道区切换到接触区时，一个镍辛烷分子可逆地从自旋 1 切换到 1/2。通过在可重复的电导测量中观察到的非弹性和弹性自旋翻转机制以及使用第一性原理计算来理解，实验证明了这种切换。我们的工作通过界面操作证明了对单个分子器件的自旋状态的主动控制。
