Synthesis, structural and dielectric properties of Ca3Mn2O7 thin films prepared by pulsed laser deposition

• Type: Article in International Scientific Journal
• Date: 2023

Authors

Silva, BM (Author) Other; Oliveira, J (Author) Other; Rebelo, T (Author) Other; Isfahani, VB (Author) Other; Rocha-Rodrigues, P (Author) Other; Lekshmi, N (Author) Other; Belo, JH (Author) FCUP; Deepak, FL (Author) Other; Lopes, AML (Author) FCUP; araujo, j. p. (Author) FCUP; Almeida, BG (Author) Other

Journal

Title: Materials Research Bulletin

Vol. 158

ISSN: 0025-5408

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 2 Citations

Scopus

Other information

Authenticus ID: P-00X-CXZ

DOI: 10.1016/j.materresbull.2022.112066

Abstract (EN): Multiferroic Ruddlesden-Popper Ca3Mn2O7 thin films were prepared by laser ablation on SrTiO3 substrates. For low laser fluences and high oxygen pressures, the films assumed the CaMnO3 Pnma orthorhombic structure. However, by increasing fluence and decreasing the oxygen pressure, the Ca3Mn2O7 phase is achieved through a post-deposition annealing treatment. Furthermore, the ferroelectric phase A21am was observed in the films, along with the orthorhombic Acaa phase, with a preferential [111] growth orientation and substrate-induced enhancement of the polar ferroelectric distortion. The dielectric permittivity shows dispersion described by the Havriliak-Negami function, and from fits to the curves, a different behavior was observed in the antiferro-magnetic region. Also, the Kohlrausch-Williams-Watts stretched exponential parameter showed an abrupt decrease below-110 K, near the Ne ' el temperature. This indicates the presence of magnetoelectric interactions and magnetically induced enhancement of dipolar correlations in the samples, favoring substrate-induced strain to enhance multiferroicity in these films.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9