@article{IurchukSchickBranetal.2016, author = {Iurchuk, V. and Schick, D. and Bran, J. and Colson, D. and Forget, A. and Halley, D. and Koc, Azize and Reinhardt, Mathias and Kwamen, C. and Morley, N. A. and Bargheer, Matias and Viret, M. and Gumeniuk, R. and Schmerber, G. and Doudin, B. and Kundys, B.}, title = {Optical Writing of Magnetic Properties by Remanent Photostriction}, series = {Physical review letters}, volume = {117}, journal = {Physical review letters}, publisher = {American Physical Society}, address = {College Park}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.117.107403}, pages = {5}, year = {2016}, abstract = {We present an optically induced remanent photostriction in BiFeO3, resulting from the photovoltaic effect, which is used to modify the ferromagnetism of Ni film in a hybrid BiFeO3/Ni structure. The 75\% change in coercivity in the Ni film is achieved via optical and nonvolatile control. This photoferromagnetic effect can be reversed by static or ac electric depolarization of BiFeO3. Hence, the strain dependent changes in magnetic properties are written optically, and erased electrically. Light-mediated straintronics is therefore a possible approach for low-power multistate control of magnetic elements relevant for memory and spintronic applications.}, language = {en} } @article{ReinhardtKocLeitenbergeretal.2016, author = {Reinhardt, Matthias and Koc, Azize and Leitenberger, Wolfram and Gaal, Peter and Bargheer, Matias}, title = {Optimized spatial overlap in optical pump-X-ray probe experiments with high repetition rate using laser-induced surface distortions}, series = {Journal of synchrotron radiation}, volume = {23}, journal = {Journal of synchrotron radiation}, publisher = {International Union of Crystallography}, address = {Chester}, issn = {1600-5775}, doi = {10.1107/S1600577515024443}, pages = {474 -- 479}, year = {2016}, abstract = {Ultrafast X-ray diffraction experiments require careful adjustment of the spatial overlap between the optical excitation and the X-ray probe pulse. This is especially challenging at high laser repetition rates. Sample distortions caused by the large heat load on the sample and the relatively low optical energy per pulse lead to only tiny signal changes. In consequence, this results in small footprints of the optical excitation on the sample, which turns the adjustment of the overlap difficult. Here a method for reliable overlap adjustment based on reciprocal space mapping of a laser excited thin film is presented.}, language = {en} }