Effect of HgO Addition on the Resistivity Behaviour of La0.75Ca0.25MnO3.

Authors :: Singh, Bharat
Kumar, Naresh
Bhatt, Masroor Ahmad
Mohan, Rajneesh
Singh, Kiran
Gaur, N. K.
Source :: AIP Conference Proceedings; 7/16/2011, Vol. 1349 Issue 1, p1063-1064, 2p
Publication Year :: 2011
Abstract: We have reported the effect of HgO addition on electrical resistivity of La<subscript>0.75</subscript>Ca<subscript>0.25</subscript>MnO<subscript>3</subscript> manganites. The samples have been synthesised by conventional solid state reaction method. The pellets of these samples were sintered at 1200° C in ambient atmosphere. These samples were characterized by X-Ray diffraction technique and low temperature four probe resistivity measurement using closed cycle helium cryostat. From XRD analysis, these samples were found to have single phase orthorhombic (Pnma) crystal structure. From the resistivity vs temperature behaviour of these samples, it has been found that the resistivity of HgO added La<subscript>0.75</subscript>Ca<subscript>0.25</subscript>MnO<subscript>3</subscript> decreases considerably in comparison to La<subscript>0.75</subscript>Ca<subscript>0.25</subscript>MnO<subscript>3</subscript>. It has also been observed that HgO addition decreases the metal-insulator transition from 242 K to 232 K which is due to cationic disorder created by HgO in La<subscript>0.75</subscript>Ca<subscript>0.25</subscript>MnO<subscript>3</subscript>. [ABSTRACT FROM AUTHOR]