A Novel [Formula: see text] × [Formula: see text] Superstructure in Epitaxially Grown 1T-TaTe2

Jinwoong Hwang; Yeongrok Jin; Canxun Zhang; Tiancong Zhu; Kyoo Kim; Yong Zhong; Ji-Eun Lee; Zongqi Shen; Yi Chen; Wei Ruan; Hyejin Ryu; Choongyu Hwang; Jaekwang Lee; Michael F Crommie; Sung-Kwan Mo; Zhi-Xun Shen

doi:10.1002/adma.202204579

A Novel $\sqrt{19}$ × $\sqrt{19}$ Superstructure in Epitaxially Grown 1T-TaTe₂

Adv Mater. 2022 Sep;34(38):e2204579. doi: 10.1002/adma.202204579. Epub 2022 Aug 20.

Authors

Jinwoong Hwang^{1

2

3}, Yeongrok Jin³, Canxun Zhang^{4

5

6}, Tiancong Zhu^{4

5}, Kyoo Kim⁷, Yong Zhong^{1

2}, Ji-Eun Lee³, Zongqi Shen⁴, Yi Chen^{4

5}, Wei Ruan^{4

5

8}, Hyejin Ryu⁹, Choongyu Hwang^{3

10}, Jaekwang Lee^{2

3

9}, Michael F Crommie^{4

5

6}, Sung-Kwan Mo², Zhi-Xun Shen^{1

11}

Affiliations

¹ Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Menlo Park, CA, 94025, USA.
² Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
³ Department of Physics, Pusan National University, Busan, 46241, South Korea.
⁴ Department of Physics, University of California, Berkeley, Berkeley, CA, 94720, USA.
⁵ Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, 94720, USA.
⁶ Kavli Energy NanoScience Institute, University of California, Berkeley, Berkeley, CA, 94720, USA.
⁷ Korea Atomic Energy Research Institute, Daejeon, 34057, South Korea.
⁸ Department of Physics, Fudan University, Fudan, 200433, China.
⁹ Center for Spintronics, Korea Institute of Science and Technology, Seoul, 02792, South Korea.
¹⁰ Quantum Matter Core-Facility, Pusan National University, Busan, 46241, South Korea.
¹¹ Geballe Laboratory for Advanced Materials, Department of Physics and Applied Physics, Stanford University, Menlo Park, CA, 94305, USA.

PMID: 35902365
DOI: 10.1002/adma.202204579

Abstract

The spontaneous formation of electronic orders is a crucial element for understanding complex quantum states and engineering heterostructures in 2D materials. A novel $\sqrt{19}$ × $\sqrt{19}$ charge order in few-layer-thick 1T-TaTe₂ transition metal dichalcogenide films grown by molecular beam epitaxy, which has not been realized, is report. The photoemission and scanning probe measurements demonstrate that monolayer 1T-TaTe₂ exhibits a variety of metastable charge density wave orders, including the $\sqrt{19}$ × $\sqrt{19}$ superstructure, which can be selectively stabilized by controlling the post-growth annealing temperature. Moreover, it is found that only the $\sqrt{19}$ × $\sqrt{19}$ order persists in 1T-TaTe₂ films thicker than a monolayer, up to 8 layers. The findings identify the previously unrealized novel electronic order in a much-studied transition metal dichalcogenide and provide a viable route to control it within the epitaxial growth process.

Keywords: angle-resolved photoemission; charge density waves; molecular beam epitaxy; tantalum ditellurides; transition metal dichalcogenides.

Abstract

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