Single- and Few-Layer WTe2 and Their Suspended Nanostructures: Raman Signatures and Nanomechanical Resonances

Abstract

Single crystal tungsten ditelluride (WTe2) has recently been discovered to exhibit non-saturating extreme magnetoresistance in bulk; it has also emerged as a new layered material from which atomic layer crystals can be extracted. While atomically thin WTe2 is attractive for its unique properties, little study has been conducted on single- and few-layer WTe2. Here we report the isolation of single- and few-layer WTe2, as well as fabrication and characterization of the first WTe2 suspended nanostructures. We have observed new Raman signatures of few-layer WTe2 that have been theoretically predicted but not yet reported to date, in both on-substrate and suspended WTe2 flakes. We have further probed the nanomechanical properties of suspended WTe2 structures by measuring their flexural resonances, and obtain a Young's modulus of E_Y~80GPa for the suspended WTe2 flakes. This study paves the way for future investigations and utilization of the multiple new Raman fingerprints of single- and few-layer WTe2, and for exploring mechanical control of WTe2 atomic layers.

12 Pages, 5 Figures in Nanoscale 8, 7854-7860 (2016)

References in corpus (10)

• Electric Field Effect in Atomically Thin Carbon Films
• Ultrahigh electron mobility in suspended graphene
• Anomalous Lattice Vibrations of Single and Few-Layer MoS2
• Valley polarization in MoS2 monolayers by optical pumping
• High Performance Single Layered WSe2 p-FETs with Chemically Doped Contacts
• Titanic Magnetoresistance in WTe2
• Superior mechanical flexibility of phosphorene and few-layer black phosphorus
• Drastic pressure effect on the extremely large magnetoresistance in WTe2: quantum oscillation study
• The electronic structure and elastic property of monolayer and bilayer transition metal dichalcogenides MX${}_2$ (M=Mo,W;X=O,S,Se,Te): A comparative first-principles study
• Raman scattering investigation of large positive magnetoresistance material WTe${}_2$

Cited by in corpus (9)

• Mechanical Properties of Atomically Thin Tungsten Dichalcogenides: WS${}_2$, WSe${}_2$ and WTe${}_2$
• Environmental Instability and Degradation of Single- and Few-Layer WTe2 Nanosheets in Ambient Conditions
• Large-Scale Arrays of Single- and Few-Layer MoS2 Nanomechanical Resonators
• Atomic Layer MoS2-Graphene van der Waals Heterostructure Nanomechanical Resonators
• Intrinsic Phonon Bands in High-Quality Monolayer T' Molybdenum Ditelluride
• Determination of the thickness and orientation of few-layer tungsten ditelluride using polarized Raman spectroscopy
• Effect of aging-induced disorder on the quantum transport properties of atomically thin WTe${}_2$
• Light-tunable charge density wave orders in MoTe2 and WTe2 single layers
• Raman spectrum of 1T'-WTe2 under tensile strain: A first-principles prediction