DOI: 10.1002/adma.201804428. Enhanced Spontaneous Polarization in Ultrathin SnTe Films with Layered Antipolar Structure

Enhanced Spontaneous Polarization in Ultrathin SnTe Films with Layered Antipolar Structure

10.1002/adma.201804428

Crossref journal-article

Wiley

Advanced Materials (311)

Abstract

Abstract2D SnTe films with a thickness of as little as 2 atomic layers (ALs) have recently been shown to be ferroelectric with in‐plane polarization. Remarkably, they exhibit transition temperatures (Tc ) much higher than that of bulk SnTe. Here, combining molecular beam epitaxy, variable temperature scanning tunneling microscopy, and ab initio calculations, the underlying mechanism of the Tc enhancement is unveiled, which relies on the formation of γ‐SnTe, a van der Waals orthorhombic phase with antipolar inter‐layer coupling in few‐AL thick SnTe films. In this phase, 4n − 2 AL (n = 1, 2, 3…) thick films are found to possess finite in‐plane polarization (space group Pmn21), while 4n AL thick films have zero total polarization (space group Pnma). Above 8 AL, the γ‐SnTe phase becomes metastable, and can convert irreversibly to the bulk rock salt phase as the temperature is increased. This finding unambiguously bridges experiments on ultrathin SnTe films with predictions of robust ferroelectricity in GeS‐type monochalcogenide monolayers. The observed high transition temperature, together with the strong spin‐orbit coupling and van der Waals structure, underlines the potential of atomically thin γ‐SnTe films for the development of novel spontaneous polarization‐based devices.

Bibliography

Chang, K., Kaloni, T. P., Lin, H., BedoyaâPinto, A., Pandeya, A. K., Kostanovskiy, I., Zhao, K., Zhong, Y., Hu, X., Xue, Q., Chen, X., Ji, S., BarrazaâLopez, S., & Parkin, S. S. P. (2018). Enhanced Spontaneous Polarization in Ultrathin SnTe Films with Layered Antipolar Structure. Advanced Materials, 31(3). Portico.

Authors 14

Kai Chang (first)
Thaneshwor P. Kaloni (additional)
Haicheng Lin (additional)
Amilcar Bedoya‐Pinto (additional)
Avanindra K. Pandeya (additional)
Ilya Kostanovskiy (additional)
Kun Zhao (additional)
Yong Zhong (additional)
Xiaopeng Hu (additional)
Qi‐Kun Xue (additional)
Xi Chen (additional)
Shuai‐Hua Ji (additional)
Salvador Barraza‐Lopez (additional)
Stuart S. P. Parkin (additional)

References 47 Referenced 114

Dates

Type	When
Created	6 years, 9 months ago (Nov. 2, 2018, 3:39 a.m.)
Deposited	1 year, 11 months ago (Sept. 10, 2023, 6:12 p.m.)
Indexed	1 day, 13 hours ago (Aug. 23, 2025, 9:36 p.m.)
Issued	6 years, 9 months ago (Nov. 2, 2018)
Published	6 years, 9 months ago (Nov. 2, 2018)
Published Online	6 years, 9 months ago (Nov. 2, 2018)
Published Print	6 years, 7 months ago (Jan. 1, 2019)

Funders 4

Deutsche Forschungsgemeinschaft 10.13039/501100001659
Region: Europe
gov (National government)
Labels3
1. German Research Association
2. German Research Foundation
3. DFG
Awards1
1. 1812/2‐1
National Natural Science Foundation of China 10.13039/501100001809
Region: Asia
gov (National government)
Labels11
1. Chinese National Science Foundation
2. Natural Science Foundation of China
3. National Science Foundation of China
4. NNSF of China
5. NSF of China
6. 国家自然科学基金委员会
7. National Nature Science Foundation of China
8. Guójiā Zìrán Kēxué Jījīn Wěiyuánhuì
9. NSFC
10. NNSF
11. NNSFC
Awards1
1. 51561145005
Ministry of Science and Technology of the People's Republic of China 10.13039/501100002855
Region: Asia
gov (National government)
Labels6
1. Chinese Ministry of Science and Technology
2. Ministry of Science & Technology, People Republic of China
3. 中华人民共和国科学技术部
4. Ministry of Science and Technology (China)
5. State Science and Technology Commission
6. MOST
Awards1
1. 2016YFA0301002
U.S. Department of Energy 10.13039/100000015
Region: Americas
gov (National government)
Labels8
1. Energy Department
2. Department of Energy
3. United States Department of Energy
4. ENERGY.GOV
5. US Department of Energy
6. USDOE
7. DOE
8. USADOE
Awards1
1. DE‐SC0016139

BibTeX

@article{Chang_2018, title={Enhanced Spontaneous Polarization in Ultrathin SnTe Films with Layered Antipolar Structure}, volume={31}, ISSN={1521-4095}, url={http://dx.doi.org/10.1002/adma.201804428}, DOI={10.1002/adma.201804428}, number={3}, journal={Advanced Materials}, publisher={Wiley}, author={Chang, Kai and Kaloni, Thaneshwor P. and Lin, Haicheng and Bedoya‐Pinto, Amilcar and Pandeya, Avanindra K. and Kostanovskiy, Ilya and Zhao, Kun and Zhong, Yong and Hu, Xiaopeng and Xue, Qi‐Kun and Chen, Xi and Ji, Shuai‐Hua and Barraza‐Lopez, Salvador and Parkin, Stuart S. P.}, year={2018}, month=nov }

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