@article{koohfar_ozbek_bland_zhang_kumah_2021, title={Interface-driven magnetic anisotropy in relaxed La0.7Sr0.3CrO3/La0.7Sr0.3MnO3 heterostructures on MgO}, volume={129}, ISSN={["1089-7550"]}, url={https://doi.org/10.1063/5.0033236}, DOI={10.1063/5.0033236}, abstractNote={We investigate the structural and magnetic properties of La0.7Sr0.3CrO3 (LSCO)/La0.7Sr0.3MnO3 (LSMO) heterostructures grown on (001)-oriented MgO by molecular beam epitaxy. Due to the large film-substrate lattice mismatch, strain relaxation is found to occur within the first 2–3 unit cells (uc) of the film as evidenced by reflection high energy electron diffraction and high-resolution synchrotron x-ray reciprocal space mapping. We find that the presence of the LSCO spacer and capping layers leads to ferromagnetism in ultra-thin LSMO layers with thicknesses of the order of 2 uc with the magnetic easy axis oriented in the film plane. Net magnetic moments of 1.4 and 2.4 μB/Mn are measured for (2 uc LSCO/2 uc LSMO) and (2 uc LSCO/4 uc LSMO) superlattices, respectively, by superconducting quantum interference device magnetometry. The effective magnetic anisotropy of the relaxed (2 uc LSCO/4 uc LSMO) heterostructure is found to be an order of magnitude higher than bulk LSMO highlighting the critical role of interfacial interactions in tuning magnetic anisotropy at complex oxide interfaces.}, number={5}, journal={JOURNAL OF APPLIED PHYSICS}, author={Koohfar, Sanaz and Ozbek, Yasemin and Bland, Hayden and Zhang, Zhan and Kumah, Divine P.}, year={2021}, month={Feb} }
 @article{koohfar_georgescu_penn_lebeau_arenholz_kumah_2019, title={Confinement of magnetism in atomically thin La0.7Sr0.3CrO3/La0.7Sr0.3MnO3 heterostructures}, volume={4}, ISSN={2397-4648}, url={http://dx.doi.org/10.1038/s41535-019-0164-1}, DOI={10.1038/s41535-019-0164-1}, abstractNote={Abstract}, number={1}, journal={npj Quantum Materials}, publisher={Springer Science and Business Media LLC}, author={Koohfar, Sanaz and Georgescu, Alexandru B. and Penn, Aubrey N. and LeBeau, James M. and Arenholz, Elke and Kumah, Divine P.}, year={2019}, month={May} }
 @article{koohfar_disa_marshall_walker_ahn_kumah_2017, title={Structural distortions at polar manganite interfaces}, volume={96}, ISSN={["2469-9969"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85027360935&partnerID=MN8TOARS}, DOI={10.1103/physrevb.96.024108}, abstractNote={Electronic, lattice, and spin interactions at the interfaces between crystalline complex transition metal oxides can give rise to a wide range of functional electronic and magnetic phenomena not found in bulk. At hetero-interfaces, these interactions may be enhanced by combining oxides where the polarity changes at the interface. The physical structure between non-polar SrTiO$_3$ and polar La$_{1-x}$Sr$_x$MnO$_3$(x=0.2) is investigated using high resolution synchrotron x-ray diffraction to directly determine the role of structure in compensating the polar discontinuity. At both the oxide-oxide interface and vacuum-oxide interfaces, the lattice is found to expand and rumple along the growth direction. The SrTiO$_3$/La$_{1-x}$Sr$_x$MnO$_3$ interface also exhibits intermixing of La and Sr over a few unit cells. The results, hence, demonstrate that polar distortions and ionic intermixing coexist and both pathways play a significant role at interfaces with polar discontinuities.}, number={2}, journal={PHYSICAL REVIEW B}, author={Koohfar, S. and Disa, A. S. and Marshall, M. S. J. and Walker, F. J. and Ahn, C. H. and Kumah, D. P.}, year={2017}, month={Jul} }