Structural, electrical and magnetic properties of magnetoelectric GdMnO3 thin films prepared by a sol-gel method

• Tipo: Artigo em Revista Científica Internacional
• Data: 2014

Autores

Romaguera Barcelay, Y (Autor) Outra; Agostinho Moreira, JA (Autor) FCUP; Almeida, A (Autor) FCUP; Tavares, PB (Autor) Outra; Perez de la Cruz, JP (Autor) Outra

Revista

Título: Thin Solid Films

Vol. 564

Páginas: 419-425

ISSN: 0040-6090

Editora: Elsevier

Indexação

ISI Web of Knowledge - 25 Citações

Scopus - 25 Citações

Classificação Científica

FOS: Ciências da engenharia e tecnologias > Engenharia dos materiais

Outras Informações

ID Authenticus: P-009-NVS

DOI: 10.1016/j.tsf.2014.06.007

Abstract (EN): In this work, we analyzed GdMnO3 magnetoelectric thin films prepared by a general sol-gel method. The film formation temperature is analyzed by a thermogravimetric analysis, while the lattice parameters of the Pbnm orthorhombic films are determined from the analysis of the X-ray spectra. The X-ray results also reveal that GdMnO3 films are under compression along the b axis. The lattice dynamic analysis carried out by a Raman spectroscopy confirms the formation of films with a Pbnm orthorhombic structure. Moreover, the analysis of the Raman spectra suggests that besides film-substrate interaction, texture and grain size influence can alter lattice dynamics relative to the bulk ones. Magnetic measurements show that the film response is different from that observed in ceramic and single crystal; mainly, in the shape and temperature where the transitions are taking place. The magnetic study also reveals that GdMnO3 films are paramagnetic above 80 K, showing a ferromagnetic-like response at low temperatures (T <= 15 K). The dielectric analysis carried out on the 850 degrees C annealed film shows the formation of a relaxation process at low temperature, which is associated with a polaronic process. Moreover, it is also observed a small anomaly at T similar to 27 K that might be related to the magnetic transition taking place in this temperature range.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7