Epitaxial growth and polarization reversal characteristics of hybrid improper ferroelectric Ca3Ti2O7 thin films
Source abstract
Abstract
Layered perovskite oxides A3B2O7 with Ruddlesden–Popper structures have attracted great attention due to their intriguing hybrid improper ferroelectricity. In this work, we prepared high-quality epitaxial Ca3Ti2O7 (CTO) thin films on Nb-SrTiO3 (STO) and Pt–Si substrates by pulsed laser deposition. The epitaxial relationship between the CTO thin film and Nb-STO substrate is [010]CTO//[010]Nb-STO, while the CTO film on Pt–Si is the polycrystalline growth with the preferred orientation of (010). The piezoelectric force microscopy image is attested to the stable existence of ferroelectricity in CTO films at room temperature with different growth patterns. A resistive switching behavior with at least two orders of magnitude is observed in CTO films driven by their ferroelectric polarization reversal. Moreover, a downward self-poling phenomenon is observed in CTO films on different substrates, and the flexoelectric effect induced by the strain gradient is supposed to be the main origin.
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Research context
OpenAlex topics: Ferroelectric and Piezoelectric Materials · Multiferroics and related materials · Advanced Sensor and Energy Harvesting Materials
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
College of Physics and Material Science, Tianjin Normal University 1 , Tianjin 300387, China
Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparing Technology, School of Science, Tianjin University 2 , Tianjin 300072, China
Funding
National Key Research and Development Program of China · National Science Foundation of Tianjin, China · National Natural Science Foundation of China
References (25)
Show source-provided references
1. Direct-write piezoelectric polymeric nanogenerator with high energy conversion efficiency10.1021/nl9040719 ↗
2. Exploiting dimensionality and defect mitigation to create tunable microwave dielectrics10.1038/nature12582 ↗
3. Ferroelectric memories10.1126/science.246.4936.1400 ↗
4. Improper ferroelectricity in perovskite oxide artificial superlattices10.1038/nature06817 ↗
5. Negative thermal expansion in hybrid improper ferroelectric Ruddlesden-Popper perovskites by symmetry trapping10.1103/PhysRevLett.114.035701 ↗
6. Hybrid improper ferroelectricity: A mechanism for controllable polarization-magnetization coupling10.1103/physrevlett.106.107204 ↗
7. Experimental demonstration of hybrid improper ferroelectricity and the presence of abundant charged walls in (Ca, Sr)3Ti2O7 crystals10.1038/nmat4168 ↗
8. Topological defects at octahedral tilting plethora in bi-layered perovskites10.1038/npjquantmats.2016.17 ↗
9. Epitaxial-strain-induced polar-to-nonpolar transitions in layered oxides10.1038/nmat4664 ↗
10. Ultra-low coercive field of improper ferroelectric Ca3Ti2O7 epitaxial thin films10.1063/1.4974217 ↗
11. Nanoscale imaging of ferroelectric domain and resistance switching in hybrid improper ferroelectric Ca3Ti2O7 thin films10.1016/j.physleta.2020.126609 ↗
12. Structure determinations for Ca3Ti2O7, Ca4Ti3O10, Ca3.6Sr0.4Ti3O10 and a refinement of Sr3Ti2O710.1107/s0108768190013416 ↗
13. Lattice match: An application to heteroepitaxy10.1063/1.333084 ↗
14. Strain and morphology control over electrical behavior of pulsed laser deposited BiFeO3 films10.1016/j.tsf.2017.11.012 ↗
15. Domain growth kinetics in lithium niobate single crystals studied by piezoresponse force microscopy10.1063/1.1845594 ↗
16. Room-temperature ferroelectric resistive switching in ultrathin Pb(Zr0.2Ti0.8)O3 films10.1021/nn2018528 ↗
17. Upward ferroelectric self-polarization induced by compressive epitaxial strain in (001) BaTiO3 films10.1063/1.4807794 ↗
18. Upward ferroelectric self-poling in (001) oriented PbZr0.2Ti0.8O3 epitaxial films with compressive strain10.1063/1.4840595 ↗
19. Ferroelectricity and self-polarization in ultrathin relaxor ferroelectric films10.1038/srep19965 ↗
20. Interface control of bulk ferroelectric polarization10.1073/pnas.1117990109 ↗
21. Mechanical writing of ferroelectric polarization10.1126/science.1218693 ↗
22. Flexoelectric effect in the reversal of self-polarization and associated changes in the electronic functional properties of BiFeO3 thin films10.1002/adma.201301601 ↗
23. Giant flexoelectric effect in ferroelectric epitaxial thin films10.1103/PhysRevLett.107.057602 ↗
24. A resistive memory in semiconducting BiFeO3 thin-film capacitors10.1002/adma.201004317 ↗
25. Electric modulation of conduction in multiferroic Ca-doped BiFeO3 films10.1038/nmat2432 ↗