Magnetoresistive and magnetic properties of elelctrospun La1−xSrxMnO3 nanowires
Thomas Karwoth, Xian Lin Zeng, Andrew Kostrubanic, Michael Koblischka, and Uwe Hartmann
Institute of Experimental Physics, Saarland University, P.O.Box 151150, D-66041 Saarbrücken, Germany
Drexel University, Philadelphia, Pennsylvania 19104, USA
Nanowires of the material class La1−xSrxMnO3 with different doping levels x= 0.2, 0.33, 0.5 were fabricated employing a sol-gel-process via electrospinning and a subsequent thermal treatment process based on thermal gravity analysis results. Investigations by means of scanning electron microscopy revealed an average diameter of the resulting nanowires of around 220 nm and a length of more than 50 µm. The chemical phases of the samples have been confirmed via X-Ray diffraction. The nanowires are polycrystalline with a grain size of about 15-17 nm, which corresponds to the result obtained from transmission electron microscopy. Analyses of the electronic transportation properties and of the magnetoresistive effects of the nanowire samples were carried out by a four probe measurement inside a bath cryostat. Of interest are size effects and the dependence of the properties on the stoichiometry. SQUID measurements of M(T) and M(H) at room temperature, 77 K and 4.2 K were carried out as well, revealing the soft magnetic character of the nanowires.