Structural, electronic and magnetic investigations on PLD based La2Ni1-xFexMnO6 disordered thin films

Department of Physics, The Institute of Science, 15 Madam Cama Rd, Mumbai, 400020, India

Adv. Mater. Lett., 2017, 8 (10), pp 958-964

DOI: 10.5185/amlett.2017.1518

Publication Date (Web): Jul 22, 2017

Copyright © IAAM-VBRI Press

E-mail: sbk_physics@yahoo.com

Abstract

The double perovskite materials show the magnetic semiconductor, magneto-optic and magneto-capacitance like interesting properties. It is predicted that the B-site substitution in this system may results in interesting properties. La₂Ni_1-xFe_xMnO₆ thin films are deposited on Pt/Ti/ Si(100) substrate  by Pulse Laser Deposition (PLD) technique. The films were uniform, fine grain and stoichiometric deposited at very low O₂ pressure. The XRD of La₂Ni_1-xFe_xMnO₆ thin films exhibits rhombohedral (R-3) phase. The peak broadening appears in Raman spectra at antistretching (518 cm^-1) and stretching (656 cm^-1) modes with presence of overtone modes at 1308 cm^-1 in La₂Ni_1-xFe_xMnO₆ thin film samples. XPS analysis reveals the presence of La³⁺, NiO, Ni³⁺, Fe³⁺, Mn³⁺ and oxygen vacancies in samples. The Ni³⁺ and Mn³⁺ antiferromagnetic coupling is responsible for decrease in saturation magnetization M_s from 4.78 to 2.74 µ_B/f.u as Fe substitution increases from 0.1 to 0.3 at 5K. The increase in grain size, peak broadening and decrease in magnetization of La₂Ni_1-xFe_xMnO₆thin film samples suggest presence of antisite defects and antisite phase boundary. The present work will helpful to study the effect of B site substitution on La₂NiMnO₆ thin films structural, electronic and magnetic properties in order to make it suitable candidate for potential applications. 

Keywords

Double perovskite, PLD, raman spectra, antisite defects, antisite phase boundary.