Polymer Coated Manganites and Its Magnetic Properties
K. Gupta1, P. T. Das2, T. K. Nath3, P. C. Jana4, A. K. Meikap5

1Kajal Gupta, Department of Physics, National Institute of Technology, Mahatma Gandhi Avenue, Durgapur-713209, West Bengal, India.
2Proloy T. Das, Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur-721302 West Bengal, India.
2Tapan K. Nath, Department of Physics and Meteorology, Indian Institute of Technology, Kharagpur-721302 West Bengal, India.
3Paresh C. Jana, Department of Physics and Technophysics, Vidyasagar University, Midnapore 721102, West Bengal, India.
4Ajit K. Meikap, Department of Physics, National Institute of Technology, Mahatma Gandhi Avenue, Durgapur-713209, West Bengal, India. 

Manuscript received on April 11, 2012. | Revised Manuscript received on April 14, 2012. | Manuscript published on May 05, 2012. | PP: 246-250 | Volume-2 Issue-2, May 2012 . | Retrieval Number: B0571042212/2012©BEIESP
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© The Authors. Published By: Blue Eyes Intelligence Engineering and Sciences Publication (BEIESP). This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Abstract: Synthesis and analysis of magnetic properties of polypyrrole coated La0.9-xSmxSr0.1MnO3 (x= 0.2) nanoparticles is the main aim of this investigation. About 60% magneto resistance (MR) is obtained for La0.9-xSmxSr0.1MnO3 nanoparticles and it decreases with increasing temperature. Enhanced spin-polarized tunneling between two adjacent grains at the grain boundary may increase the MR. Oscillating type of MR is obtained for polypyrrole coated La0.9-xSmxSr0.1MnO3 . A core shell type model is attributed to an intermediate exchange coupling between the shell (surrounding) and antiferromagnetic core mainly on the basis of uncompensated surface spins. Samples may be used as multifunctional spintronic devices and magnetic recording medium.

Keywords: A. Manganites, B. Polypyrrole, C. Oscillating magneto resistance