Controlled spin switching in a metallocene molecular junction

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.This work has been supported by the Agence Nationale de la Recherche (Grant Nos. ANR-13-BS10-0016, ANR-11-LABX-0058 NIE, ANR-10-LABX-0026 CSC) the ANPCyT project PICT Bicentenario No. 1962, the CONICET project PIP 0667, and the UNR project PID ING235. We acknowledge computer time provided by the CCT-Rosario Computational Center and the Computational Simulation Center (CSC) for Technological Applications, members of the High Performance Computing National System (SNCAD, MincyT-Argentina). Financial support from MINECO MAT2015-66888-C3-2-R and FEDER funds is also gratefully acknowledged.Peer Reviewe

Controlled spin switching in a metallocene molecular junction

Manipulating spin states of molecules in a controllable manner is essential to develop the molecule-based spintronics technologies. Here, Ormaza et al. show how to use the interaction between a single metallocene molecule and a metallic surface to reversibly switch spin from 1 to ½ in a junction