The nanoscale electro-reduction in a memristive oxide is a highly relevant fi eld for future non-volatile memory materials. Photoemission electron microscopy is used to identify the conducting fi laments and correlate them to structural features of the top electrode that indicate a critical role of the three phase boundary (electrode-oxide-ambient) for the electro-chemical reduction. Based on simulated temperature profi les, the essential role of Joule heating through localized currents for electro-reduction and morphology changes is demonstrated.

Full electric-field control of spin orientations is one of the key tasks in semiconductor spintronics. We demonstrate that electric-field pulses can be utilized for phase-coherent ±π spin rotation of optically generated electron spin packets in InGaAs epilayers detected by time-resolved Faraday rotation. Through spin-orbit interaction, the electric-field pulses act as local magnetic field pulses. By the temporal control of the local magnetic field pulses, we can turn on and off electron spin precession and thereby rotate the spin direction into arbitrary orientations in a two-dimensional plane. Furthermore, we demonstrate a spin-echo-type spin drift experiment and find an unexpected partial spin rephasing, which is evident by a doubling of the spin dephasing time.

″ −during resistive switching are suggested. These fi ndings are discussed with regard to the point defect structure of the fi lm and the local oxidation of the donor-doped substrate. In particular, the apparent dichotomy between the observation of acceptor-type defects and increased electronic conductivity in STO is addressed.

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