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Electric-field modulating exchange bias and near 180° deterministic magnetization switching at room temperature are demonstrated in simple antiferromagnetic/ferromagnetic/ferroelectric (AFM/FM/FE) exchange-coupled multiferroic multilayers of IrMn/Co/PZT. A rather large exchange bias field shift up to ?Hex/Hex= 500% was obtained. This change governs mainly the electric-field strength rather than the applied current. It is explained as being realized through the competition between the electric-field induced uniaxial and unidirectional anisotropies. These results show good prospects for low-power spintronic devices.

In this paper, we have investigated an alternative method to obtain well-organized silicon nanowires grown by vapor-liquid-solid process. We have studied the influence of the droplet size on the growth direction of nanowires on plain wafers. By using self-organized Au droplets grown by molecular beam epitaxy on vicinal Si(111) surface with a 2deg miscut towards the [11-2] crystallographic direction, we have obtained well organized gold droplets along the steps with small size dispersion. The growth of Si nanowires from these droplets allows defining a critical diameter for changing the Si nanowires growth direction. When the gold droplet diameter is larger than 100 nm, Si nanowires exhibit a <111> orientation and remain free of structural defects. The localisation of Si nanowires was performed in nanoscale silicon seeds formed by modified local oxidation of silicon process. This approach, based on a simple and reliable method, enable the organisation of Si nanowires with <111> orientation on Si(001) substrates.