Studies on structural and magnetic properties of NdFeO 3 single crystals grown by optical floating zone technique
- PDF / 1,175,312 Bytes
- 7 Pages / 595.276 x 790.866 pts Page_size
- 110 Downloads / 230 Views
Bull Mater Sci (2020) 43:285 https://doi.org/10.1007/s12034-020-02259-4
Sadhana(0123456789().,-volV)FT3](012345 6789().,-volV)
Studies on structural and magnetic properties of NdFeO3 single crystals grown by optical floating zone technique T SHALINI1, P VIJAYAKUMAR2 and J KUMAR3,* 1
Crystal Growth Centre, Anna University, Chennai 600025, India X-ray Scattering and Crystal Growth Section, Material Science Group, IGCAR, Kalpakkam 603102, India 3 UGC-BSR Faculty Fellow, Crystal Growth Centre, Anna University, Chennai 600025, India *Author for correspondence ([email protected]) 2
MS received 1 April 2020; accepted 16 June 2020 Abstract. NdFeO3 single crystals have been grown by optical floating-zone technique using Nd2O3 and Fe2O3 as the source by solid-state reaction method. The crystalline structure of NdFeO3 belongs to orthorhombic symmetry and the presence of a distorted perovskite structure was confirmed by powder X-ray diffraction (XRD) analysis. From the XRD results, it is visualized that the lattice expansion has been observed in the unit cell parameters which may appear due to interstitial defects in the NdFeO3 matrix. The deficiency of oxygen atoms and the presence of excess Fe ions in NdFeO3 have been confirmed with EDX spectra. The spin-reorientation region (T = 120 K) exhibits lower coercive field and the hysteresis loops depict enhanced magnetization (Ms and Mr) values of NdFeO3 single crystal. Presence of compensation temperature point at Tcomp = 7.5 K denotes the anti-parallel alignment of rare-earth ions with Fe magnetic moments. At high temperatures, Fe3? magnetic moments show strong antiferromagnetic interactions ensuing in Neel temperature (TN) at 690 K. Keywords.
1.
Crystal growth; solid-state reaction; optical floating zone; spin re-orientation; Neel temperature.
Introduction
The rare earth orthoferrites (RFeO3) of perovskite structure have attracted much attention owing to its wide applications in solid-oxide fuel cells, magneto-optical materials, catalysts and gas sensors [1–4]. They exhibit long range multiferroic property at room temperature due to the super exchange interactions between Fe3? and R3? magnetic sublattices, leading to potential applications in actuation, memory and sensing portfolios [5]. Also, these magnetic interactions give rise to properties, such as high domain wall velocity, weak ferromagnetism and spin re-orientation phenomena (SR) for magnetic field sensors, magneto-optical data storage applications, etc. [6]. NdFeO3, a distorted perovskite-structured RFeO3 compound, crystallizes orthorhombically with the space group Pbnm. It has Nd3? ions at the centre surrounded by FeO6 octahedral arrangement as depicted by using the tilting Glazer system a?a-a[7–9]. The magnetic symmetry as per Bertaut notation has been denoted as GxAyFz, where Nd magnetic moments follow C-type antiferromagnetic ordering with Gx configuration at TN = 1.5 K [9,10]. The magnetic ordering of Fe3? ions exhibit G-type canted antiferromagnetism below the Neel temperature (TN) at about 690 K. In add
Data Loading...
