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Title: Phase Transition of MoTe 2 Controlled in van der Waals Heterostructure Nanoelectromechanical Systems
Abstract

This work reports experimental demonstrations of reversible crystalline phase transition in ultrathin molybdenum ditelluride (MoTe2) controlled by thermal and mechanical mechanisms on the van der Waals (vdW) nanoelectromechanical systems (NEMS) platform, with hexagonal boron nitride encapsulated MoTe2structure residing on top of graphene layer. Benefiting from very efficient electrothermal heating and straining effects in the suspended vdW heterostructures, MoTe2phase transition is triggered by rising temperature and strain level. Raman spectroscopy monitors the MoTe2crystalline phase signatures in situ and clearly records reversible phase transitions between hexagonal 2H (semiconducting) and monoclinic 1T′ (metallic) phases. Combined with Raman thermometry, precisely measured nanomechanical resonances of the vdW devices enable the determination and monitoring of the strain variations as temperature is being regulated by electrothermal control. These results not only deepen the understanding of MoTe2phase transition, but also demonstrate a novel platform for engineering MoTe2phase transition and multiphysical devices.

 
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Award ID(s):
1809770 1904580 2203625
NSF-PAR ID:
10394836
Author(s) / Creator(s):
 ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Small
Volume:
19
Issue:
5
ISSN:
1613-6810
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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