Dataset Information

Epitaxial Stabilization and Persistent Nucleation of the 3C Polymorph of Ba_0.6Sr_0.4MnO₃.

ABSTRACT: Ba-rich compositions in the Ba_xSr_1-xMnO₃ (BSMO) cubic perovskite (3C) system are magnetic ferroelectrics and are of interest for their strong magnetoelectric coupling. Beyond x = 0.5, they only form in hexagonal polymorphs. Here, the 3C phase boundary is pushed to Ba_0.6Sr_0.4MnO₃ for the thin films. Using regular pulsed laser deposition (rPLD), 3C Ba_0.6Sr_0.4MnO₃ could be epitaxially stabilized on DyScO₃ (101)_o substrates by using a 0.1% O₂/99.9% N₂ gas mixture. However, the 3C phase was mixed with the 4H polymorph for films 24 nm thick and above, and the films were relatively rough. To improve flatness and phase purity, changes in growth kinetics were investigated and interval PLD (iPLD) was especially effective. In iPLD, deposition is interrupted after completion of approximately one monolayer, and the deposit is annealed for a specific period of time before repeating. Both film flatness and, more importantly, the volume of the 3C polymorph improved with iPLD, resulting in 40 nm single-phase films. The results imply that iPLD improves the persistent nucleation of highly metastable phases and offers a new approach to epitaxial stabilization of novel materials, including more Ba-rich BSMO compositions in the 3C structure.

SUBMITTER: Zhou C

PROVIDER: S-EPMC10835664 | biostudies-literature | 2024 Jan

REPOSITORIES: biostudies-literature

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Epitaxial Stabilization and Persistent Nucleation of the 3C Polymorph of Ba0.6Sr0.4MnO3.

Zhou Catherine C Evans Charles C Dickey Elizabeth C EC Rohrer Gregory S GS Salvador Paul A PA

ACS applied materials & interfaces 20240117 4

Ba-rich compositions in the BaxSr1-xMnO3 (BSMO) cubic perovskite (3C) system are magnetic ferroelectrics and are of interest for their strong magnetoelectric coupling. Beyond x = 0.5, they only form in hexagonal polymorphs. Here, the 3C phase boundary is pushed to Ba0.6Sr0.4MnO3 for the thin films. Using regular pulsed laser deposition (rPLD), 3C Ba0.6Sr0.4MnO3 could be epitaxi ...[more]

PMID: 38232043

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Dataset Information

Epitaxial Stabilization and Persistent Nucleation of the 3C Polymorph of Ba_0.6Sr_0.4MnO₃.

Publications

Epitaxial Stabilization and Persistent Nucleation of the 3C Polymorph of Ba<sub>0.6</sub>Sr<sub>0.4</sub>MnO<sub>3</sub>.

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