Magnetic nanosystems
Axis 4 - Thin films of SMMs and related magnetic complexes
Engineering the magnetic coupling at the molecule/magnetic surface interface between self-assembled metal complexes and epitaxial ferrimagnetic iron oxide
We used mononuclear Co(II) and Ni(II) complexes with organic ligands terminated with phosphonate groups that allows their grafting as single layers on a Fe2O3 111 surface. The metal ions belonging to the complex are ferromagnetically coupled to the Fe surface atoms leading to a blocking of their magnetization and an opening of the hysteresis loop at zero field as demonstrated from the L2,3-edges XMCD local magnetic probe.
(a) Schematic view of the bonding between the phosphonate based Co(II) complex and the Fe2O3 111 surface ; (b) AFM image of the molecular monolayer of on Fe2O3 and (c) hysteresis loop of the single layer on the Fe (substrate) and Co (molecule) obtained from the X-ray Magnetic Circular Dichroism at the L2,3-edges of the two metals
Engineering the magnetic coupling and anisotropy at the molecule–magnetic surface interface in molecular spintronic devices. V. Campbell, M. Tonelli, I. Cimatti, J-B. Moussy, L. Tortech, Y. Dappe, E. Rivière, R. Guillot, S. Delprat, R. MAttana, P. Seneor, Ph. Ohresser, F. Choueikani, E. Otero, F. Koprowiak, V.G. Chilkuri, N. Suaud, N. Guilhéry, A. Galtayries, F. Miserque, M-A. Arrio, Ph. Sainctavit, T. Mallah (2016) Nat. Commun. 7, 13646
Molecular-scale dynamics of light-induced spin cross-over in a two-dimensional layer
Spin cross-over molecules show the unique ability to switch between two spin states when submitted to external stimuli such as temperature, light or voltage. If controlled at the molecular scale, such switches would be of great interest for the development of genuine molecular devices in spintronics, sensing and for nanomechanics. X-ray Absorption Spectroscopy studies have already been used to follow the light induced spin crossover of thin films. Here, we go a step further and observe this phenomenon by STM on a single layer of molecules allowing the access, for the first time, to the dynamics of the light induced transformation between two ordered mixed spin-state phases.
STM images (4.6 K) of the same area (a) in its initial state presenting a S1/3 superstructure, (b) under blue light illumination after 9h and 45 min of exposure and (c) in its relaxed state 9h and 45 min after stopping the blue light illumination (V = 0.3V, I = 20 pA). Scale bars, 10 nm
Molecular-scale dynamics of light-induced spin cross-over in a two-dimensional layer. K. Bairagi, O. Iasco, A. Bellec, A. Kartsev, D. Li, J. Lagoute, C. Chacon, Y. Girard, S. Rousset, F. Miserque, Y. Dappe, A. Smogunov, C. Barreteau, M-L. Boillot, T. Mallah, V. Repain (2016) Nat. Commun. 7, 12212
Last update on 06.21.2019