One-Step Growth of Bilayer 2H-1T' MoTe2 van der Waals Heterostructures with Interlayer-Coupled Resonant Phonon Vibration

Zenglong Guo; Lei Wang; Mengjiao Han; Erding Zhao; Liang Zhu; Weiteng Guo; Junyang Tan; Bilu Liu; Xing-Qiu Chen; Junhao Lin

doi:10.1021/acsnano.2c04664

One-Step Growth of Bilayer 2H-1T' MoTe₂ van der Waals Heterostructures with Interlayer-Coupled Resonant Phonon Vibration

ACS Nano. 2022 Jul 26;16(7):11268-11277. doi: 10.1021/acsnano.2c04664. Epub 2022 Jul 18.

Authors

Zenglong Guo^{1

2}, Lei Wang^{3

4}, Mengjiao Han⁵, Erding Zhao^{1

2}, Liang Zhu^{1

2}, Weiteng Guo^{1

2}, Junyang Tan⁶, Bilu Liu⁶, Xing-Qiu Chen^{3

4}, Junhao Lin^{1

2}

Affiliations

¹ Department of Physics, Shenzhen Institute for Quantum Science and Engineering (SIQSE), Southern University of Science and Technology, Shenzhen 518055, People's Republic of China.
² Shenzhen Key Laboratory of Advanced Quantum Functional Materials and Devices, Southern University of Science and Technology, Shenzhen 518055, People's Republic of China.
³ Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 110016 Shenyang, People's Republic of China.
⁴ School of Materials Science and Engineering, University of Science and Technology of China, 110016 Shenyang, People's Republic of China.
⁵ Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, People's Republic of China.
⁶ Shenzhen Geim Graphene Center, Tsinghua-Berkeley Shenzhen Institute and Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, People's Republic of China.

PMID: 35848623
DOI: 10.1021/acsnano.2c04664

Abstract

2H-1T' MoTe₂ van der Waals heterostructures (vdWHs) have promising applications in optoelectronics due to a seamlessly homogeneous semiconductor-metal coupled interface. However, the existing methods to fabricate such vdWHs involved complicated steps that may deteriorate the interfacial coupling and are also lacking precise thickness control capability. Here, a one-step growth method was developed to controllably grow bilayer 2H-1T' MoTe₂ vdWHs in the small growth window overlapped for both phases. Atomic-resolution low-voltage transmission electron microscopy shows the distinct moiré patterns in the bilayer vdWHs, revealing the epitaxial nature of the top 2H phase with the lattice parameters regulated by the underneath 1T' phase. Such epitaxially stacked bilayer vdWHs modulate the interlayer coupling by resonating their vibration modes, as unveiled by the angle-resolved polarized Raman spectroscopy and first-principles calculations.

Keywords: MoTe2; first-principles calculation; polarized Raman spectroscopy; salt-assisted CVD growth; van der Waals heterostructure.