2005/04/22 by Jitendra Kumar, Kumar, Jitendra, Rajiv K. Singh +11
Materials Science · Physics and Astronomy · #Advanced Thermoelectric Materials and Devices #FOS: Physical sciences #Magnetic Properties of Alloys #Magnetic and transport properties of perovskites and related materials #Materials Science (cond-mat.mtrl-sci) #cond-mat.mtrl-sci
paper · pdf · doi:10.48550/arxiv.cond-mat/0504579
23 pages, 9 figures, submitted to J. Mag. Magn. Materials
arxiv created 2005/04/22 · openalex publication_date 2005/04/22 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
A detailed investigation of the effect of PMMA on the structure, microstructure and magneto-transport properties of manganite La0.7Ca0.3MnO3 (LCMO) is presented. LCMO-PMMA nanostructured composites have been synthesized by a unique polymeric sol-gel route, which leads to improved solubility of PMMA in the LCMO matrix. The LCMO phase is grown in the presence of varying PMMA concentration at ~500 0 C. This route yields single phase material and the grain size is observed to decrease slightly with increasing PMMA concentration. On increasing the PMMA concentration, TC undergoes a small decrease, resistivity is observed to increase by two orders of magnitude, with a concomitant large decrease in TIM, e.g., from 218 K for virgin LCMO to 108 K for 50 wt% PMMA admixed LCMO. Low field magneto-resistance measured in the temperature range 77-300 K shows considerable enhancement as a function of the PMMA concentration. These phenomena are explained by taking into account the increased intergranular disorder as a consequence of PMMA admixture.