Switching of a Quantum Dot Spin Valve by Single Molecule Magnets

Abstract

We explore theoretically the spin transport in nanostructures consisting of a gold quantum dot bridging nonmagnetic electrodes and two Mn12-Ph single molecule magnets (SMMs) that are thiol-bonded to the dot but are not in direct contact with the electrodes. We find that reversal of the magnetic moment of either SMM by the application of a magnetic field leads to a large change in the resistance of the dot, i.e., a strong spin valve effect. We show that this phenomenon arises from a novel physical principle: The spin-dependent molecular orbitals that extend over the dot and both SMMs change drastically when the magnetic moment of either SMM is reversed, resulting in a large change in the conduction via those orbitals. The same physics may also be responsible for the spin valve phenomena discovered recently in carbon nanotube quantum dots with rare earth SMMs by Urdampilleta, Klyatskaya, Cleuziou, Ruben and Wernsdorfer [Nature Mater. 10, 502506 (2011)]

5 pages, 4 figures

References in corpus (4)

• Supramolecular Spin Valves
• Transport through quantum-dot spin valves containing magnetic impurities
• Spin Diode Behavior in Transport Through Single-Molecule Magnets
• Tight Binding Model of Mn12 Single Molecule Magnets: Electronic and Magnetic Structure and Transport Properties

Cited by in corpus (4)

• Landau-Zener tunneling of a single Tb3+ magnetic moment allowing the electronic read-out of a nuclear spin
• Valley currents and non-local resistances of graphene nanostructures with broken inversion symmetry from the perspective of scattering theory
• Mechanism of the enhanced conductance of a molecular junction under tensile stress
• Quantum turnstile operation of single-molecule magnets