Magnetic-coupled phase anomaly in mixed-phase BiFeO3 thin films
| Autor: | Ying-Hao Chu, Yi De Liou, Hsin Hua Lee, Heng Jui Liu, Yen Chin Huang, Yi-Chun Chen |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Materials science
Condensed matter physics lcsh:Biotechnology General Engineering 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences lcsh:QC1-999 Condensed Matter::Materials Science Phase (matter) lcsh:TP248.13-248.65 0103 physical sciences General Materials Science Mixed phase Anomaly (physics) Thin film 010306 general physics 0210 nano-technology lcsh:Physics |
| Zdroj: | APL Materials, Vol 5, Iss 8, Pp 086112-086112-7 (2017) |
| Popis: | The rich phase diagram of rhombohedral (R)-like and tetragonal (T)-like monoclinic polymorph in strained BiFeO3 (BFO) films brings on various functionalities. Finding correlations of physical ordering parameters in this system is generally difficult because T-like and R-like phases are undistinguishable in many aspects. In this study, the magnetic-coupled structural transitions of the mixed-phase BFO at low temperatures were investigated by atomic force microscopy (AFM), X-ray diffraction (XRD), and Raman spectroscopy. To resolve the complexity resulted from the similarity between T-like and R-like phases, we analyzed the Raman spectra on a micro-scale region with various T/R ratios, which is in situ manipulated by an AFM tip carrying a dc bias. Phonons of T-like and R-like phases were thus successfully separated. Based on temperature-dependent XRD and resolved Raman spectra, we observed two isostructural transitions at around 225 K and 150 K, and they are strongly correlated with the magnetic ordering in the mixed-phase BFO film. Moreover, through the effective spin-lattice coupling, the evolution of the T/R polymorph is changed by the magnetic cooling process at low temperatures. This study provides a pathway to modulate phonon behaviors by magnetic fields in a highly strained system. |
| Databáze: | OpenAIRE |
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