Ferromagnetism evidence and size dependence in ferroelectric PZN-4.5PT nanoparticles

¹ Laboratoire de Chimie et de Physique des Matériaux (LCPM), University, Assane Seck of Ziguinchor (UASZ) Quartier Néma 2, BP 523, Ziguinchor, Senegal
² Inserm, U1148, Laboratory for Vascular Translational Science, Université Paris 13, Sorbonne Paris Cité F-93017 Bobigny, France
³ Univ Lyon, INSA- Lyon, LGEF, EA682 - 8 rue de la Physique, F-69621, Villeurbanne, France
⁴ Institute for Nuclear Sciences Vinca, University of Belgrade - Mike Petrovica Alasa 12-14 POB 522, 11351 Vinca, Belgrade, Serbia
⁵ ESRF - 71 Avenue des Martyrs, F-38000 Grenoble, France

^(a) remindioukane@gmail.com

Received: 8 November 2018
Accepted: 14 February 2019

Abstract

In this work we show the size-dependent ferromagnetic behavior of undoped and Mn-doped PZN-4.5PT single crystals, consequently their multiferroic one. Undoped single crystals were tamisized and three different sizes powders were investigated showing a size dependence in such ferroelectric materials while no magnetism is observed for the non-oriented and oriented bulk single crystals. The results show the existence of an optimized grain sizes range () in which the magnetism is the highest (around 0.08 emu/g). It is found that the maximum value of the relative strain decreases from 0.25% for undoped crystals to 0.20% for Mn-doped ones. The remanent magnetization and coercivity () were found equal, respectively, to and 63 Oe for undoped and, and 66 Oe for Mn-doped PZN-4.5PT indicating that PZN-4.5PT particles possessed weak ferromagnetic behavior. Mn doping increases highly the spontaneous magnetization from to , respectively for undoped and Mn-doped nanoparticles.