• T SHALINI

Articles written in Bulletin of Materials Science

• Studies on structural and magnetic properties of NdFeO$_3$ single crystals grown by optical floating zone technique

NdFeO$_3$ single crystals have been grown by optical floating-zone technique using Nd$_2$O$_3$ and Fe$_2$O$_3$ as the source by solid-state reaction method. The crystalline structure of NdFeO$_3$ belongs to orthorhombic symmetry and the presence of a distorted perovskite structure was confirmed by powder X-ray diffraction (XRD) analysis. From the XRDresults, it is visualized that the lattice expansion has been observed in the unit cell parameters which may appear due to interstitial defects in the NdFeO$_3$ matrix. The deficiency of oxygen atoms and the presence of excess Fe ions in NdFeO$_3$ have been confirmed with EDX spectra. The spin-reorientation region ($T=120$ K) exhibits lower coercive field and the hysteresis loops depict enhanced magnetization ($M_{\rm s}$ and $M_{\rm r}$) values of NdFeO$_3$ single crystal. Presence of compensation temperature point at $T_{\rm comp} = 7.5$ K denotes the anti-parallel alignment of rare-earth ions with Fe magnetic moments. At high temperatures, Fe$^{3+}$ magnetic moments show strong antiferromagnetic interactions ensuing in Neel temperature ($T_{\rm N}$)at 690 K.

• Investigations on the structural and magnetic properties of Nd$_{1-x}$Gd$_x$FeO$_3$

We report on the increase in spin re-orientation transition temperature (T$_{SR}$) and Neel temperature (T$_N$) in Nd$_{0.95}$Gd$_{0.05}$FeO$_3$ compound, by substituting Gd$^{3+}$ ions at the A-site of NdFeO$_3$. Structural and magnetic properties ofNd$_{1-x}$Gd$_x$FeO$_3$ (x = 0, 0.03 and 0.05 mol%) have been analysed by employing solid-state reaction method. Crystallite size reduction and lattice contraction have been observed with increase in Gd substitution in NdFeO$_3$. $M–H$ curves depictstrong ferromagnetic behaviour of Nd$_{1-x}$Gd$_x$FeO$_3$ with a non-saturating and large coercive hysteresis loops. The crystallite size of Nd$_{1-x}Gd$_x$FeO$_3\$ influences the magnetic property, resulting in the ferromagnetic behaviour with higher M and Hc values at room temperature and low temperatures

• # Bulletin of Materials Science

Volume 45, 2022
All articles
Continuous Article Publishing mode

• # Dr Shanti Swarup Bhatnagar for Science and Technology

Posted on October 12, 2020

Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020