title: Molecular quantum spintronics: supramolecular spin valves based on single-molecule magnets and carbon nanotubes.
abstract: We built new hybrid devices consisting of chemical vapor deposition (CVD) grown carbon nanotube (CNT) transistors, decorated with TbPc(2) (Pc = phthalocyanine) rare-earth based single-molecule magnets (SMMs). The drafting was achieved by tailoring supramolecular π-π interactions between CNTs and SMMs. The magnetoresistance hysteresis loop measurements revealed steep steps, which we can relate to the magnetization reversal of individual SMMs. Indeed, we established that the electronic transport properties of these devices depend strongly on the relative magnetization orientations of the grafted SMMs. The SMMs are playing the role of localized spin polarizer and analyzer on the CNT electronic conducting channel. As a result, we measured magneto-resistance ratios up to several hundred percent. We used this spin valve effect to confirm the strong uniaxial anisotropy and the superparamagnetic blocking temperature (T(B) ~ 1 K) of isolated TbPc(2) SMMs. For the first time, the strength of exchange interaction between the different SMMs of the molecular spin valve geometry could be determined. Our results introduce a new design for operable molecular spintronic devices using the quantum effects of individual SMMs.
authors.affiliation: Institut Néel, CNRS et Université Joseph Fourier, BP 166, F-38042 Grenoble Cedex 9, France; E-Mails:  matias.urdampilleta@grenoble.cnrs.fr  (M.U.);  ngoc-viet.nguyen@grenoble.cnrs.fr  (N.-V.N.);  jean-pierre.cleuziou@grenoble.cnrs.fr  (J.-P.C.).
authors.forename: Matias
authors.initials: M
authors.lastname: Urdampilleta
authors.forename: Ngoc-Viet
authors.initials: NV
authors.lastname: Nguyen
authors.forename: Jean-Pierre
authors.initials: JP
authors.lastname: Cleuziou
authors.forename: Svetlana
authors.initials: S
authors.lastname: Klyatskaya
authors.forename: Mario
authors.initials: M
authors.lastname: Ruben
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Wernsdorfer
mesh_terms: D008280:Magnetics; D036103:Nanotechnology / Q000295:instrumentation; D037742:Nanotubes, Carbon / Q000737:chemistry*; D011789:Quantum Theory; D013696:Temperature
chemical_list: D037742:Nanotubes, Carbon
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