Dhirendra Kumar | Searcharxiv

arXiv2014

Structural studies on Multiferroic La1-xBixCrO3 Perovskites

The synthesis and structural studies on the polycrystalline La1-xBixCrO3 (x =0, 0.2, 0.25, 0.3, 0.35) have been done using XRD and TEM. The results of the Reitveld refinement of XRD data shows that these compounds crystallize in an orthorhombic structure with Pnma space group. With increasing Bi content, the unit cell volume and lattice parameters undergo non monotonous changes within the tolerance factor from 0.84092 to 0.84072. This has been attributed to the anisotropy induced by lone pair of Bi3+, which may distorted the lattice.

cond-mat.str-el↗

arXiv2011

Glass-like kinetic arrest of first-order structural phase transition in LaxMnO3{\pm}δ (x= 1 & 0.9)

We report here the occurrence of glass-like kinetic-arrest of first-order phase transition of R-3c to Pbnm in a supercooled LaxMnO3\pmδ (X= 1 & 0.9 and δ>0.125) below its insulator-metal transition employing low-temperature transmission electron microscopy (TEM) and x-ray diffraction. No transformation was observed even in a ~12 hrs aged LaxMnO3\pmδ at 98K until unless it was triggered insitu using e-beam irradiation in TEM. A systematic triggering at different temperatures has revealed the occurrence of kinetic-arrest situation similar to stable glass-formers. This has been attributed to the suppression of Johan-Teller distortion by double exchange. PACS number(

cond-mat.str-el↗