Anisotropic magneto-Coulomb effects and magnetic single-electron-transistor action in a single nanoparticle

A present challenge in the field of spintronics is the study of spin-dependent transport in nanodevices where all dimensions are reduced to only a few nanometres. The archetypical device structure used to explore spin transport at such a scale consists of a nanometre-sized object such as a molecule, quantum dot or nanotube connected by ferromagnetic contacts. New magneto-Coulomb effects are expected as a consequence of the interaction between charge and spin degrees of freedom. However, the focus has been mainly theoretical up to now with a lack of results on the experimental side. More importantly, in most of the studies the influence of the ferromagnetic electrodes has been largely overlooked. Here, we demonstrate that a significant magneto-Coulomb effect can be induced by conventional magnetic electrodes and mimic spin-valve magnetoresistance. Moreover, we show that the magnetic electrode can act as a gate leading to a ferromagnetic single-electron transistor with only two terminals.