Effects of vanadium doping on the charge ordering and low-temperature spin-glass phase in Pr0.45Ca0.55MnO3

• Published in: Journal of alloys and compounds 2022-11, Vol.921, p.166048, Article 166048
• Main Authors: Debnath, Mintu, Biswas, Bhaskar, Bose, Esa, Charan Das, Sambhu, Chatterjee, Souvik, Pal, Sudipta
• Format: Article
• Language: English
• Subjects: Antiferromagnetism; Charge ordering; Crystal structure; Current carriers; Dielectric properties; Ferroelectricity; Ferromagnetism; Grain boundaries; High temperature; Low temperature; Magnetic properties; Magnetization; Perovskite structure; Phase transitions; Spin glasses; Vanadium; Vanadium doping
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2022.166048

We report structural, magnetic, and dielectric properties of the Pr0.45Ca0.55Mn1-xVxO3 (x = 0.05 and 0.1) polycrystalline compounds, prepared by solid state reaction method. Pnma space group and orthorhombic crystal structure of the compounds are confirmed by the Rietveld refinement of X-ray diffraction data. Magnetic study reveals a multiple-phase-separated metastable magnetic behavior with charge ordered phase followed by a spin-glass state at the low-temperature region. For a single change of vanadium content from x = 0.05–0.1, the charge ordering temperature decreases from 245 K to 239 K, the antiferromagnetic ordering temperature decreases from 131 K to 127 K, and the ferromagnetic cluster-glass ordering temperature increases from 41 K to 44 K. This indicates the weakening of charge ordering strength and development of ferromagnetic components in the antiferromagnetic background, which is also confirmed by isothermal hysteresis. Colossal dielectric constant is observed in both samples. In the measured temperature range, an implication of a ferroelectric phase transition around 253 K is observed in Pr0.45Ca0.55Mn0.90V0.10O3 compound. The calculated results indicate that the low-temperature relaxation follows variable range hopping behavior, whereas the high-temperature one takes place according to the Arrhenius model. The fitting parameters ascribe the low-temperature relaxation process to the hopping of polaron charge carriers at localized sites, whereas the high-temperature relaxation is related to Maxwell-Wagner relaxation, caused by blocking of charge carriers at grain boundaries. •Pr0.45Ca0.55Mn1−xVxO3 (x = 0.05, 0.1) polycrystals are synthesized by solid state reaction method.•Pnma space group and orthorhombic structure are confirmed by Reitveld refinement of XRD data.•Charge ordering compression and low-temperature spin-glass phase enhanced with vanadium doping.•Colossal dielectric constant behavior is observed at higher temperature range.•Heating protocol exhibits two relaxations related to polaronic VRH followed by Arrhenius behavior.