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Experimental observations and density functional simulations on the structural transition behavior of a two-dimensional transition-metal dichalcogenide.

ABSTRACT: In this work, we show an obvious evidence of nondestructive Raman spectra for the structural transition, i.e., the existence of a charge density wave (CDW) in monolayer 2H-TaS₂, which can exhibit a much higher transition temperature than bulk and results in additional vibrational modes, indicating strong interactions with light. Furthermore, we reveal that the degenerate breath and wiggle modes of 2H-TaS₂ originated from the periodic lattice distortion can be probed using the optical methods. Since recently several light-tunable devices have been proposed based on the CDW phase transition of 1 T-TaS₂, our study and in particular, the theoretical results will be very helpful for understanding and designing electronic devices based on the CDW of 2H-TaS₂.

SUBMITTER: Liu W

PROVIDER: S-EPMC7588463 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Experimental observations and density functional simulations on the structural transition behavior of a two-dimensional transition-metal dichalcogenide.

Liu W W Duan Z Z Zhang C C Hu X X XX Cao J B JB Liu L J LJ Lin L L

Scientific reports 20201026 1

In this work, we show an obvious evidence of nondestructive Raman spectra for the structural transition, i.e., the existence of a charge density wave (CDW) in monolayer 2H-TaS<sub>2</sub>, which can exhibit a much higher transition temperature than bulk and results in additional vibrational modes, indicating strong interactions with light. Furthermore, we reveal that the degenerate breath and wiggle modes of 2H-TaS<sub>2</sub> originated from the periodic lattice distortion can be probed using t ...[more]

PMID: 33106537

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