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Phonon origin and lattice evolution in charge density wave states.

ABSTRACT: Metallic transition metal dichalcogenides, such as tantalum diselenide (TaSe2), display quantum correlated phenomena of superconductivity and charge density waves (CDW) at low temperatures. Here, the photophysics of 2H-TaSe2 during CDW transitions is revealed by combining temperature-dependent, low-frequency Raman spectroscopy and density functional theory (DFT). The spectra contain amplitude, phase, and zone-folded modes that are assigned to specific phonons and lattice restructuring predicted by DFT calculations with superb agreement. The non-invasive and efficient optical methodology detailed here demonstrates an essential link between atomic-scale and microscopic quantum phenomena.

SUBMITTER: Hill HM

PROVIDER: S-EPMC6774203 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Phonon origin and lattice evolution in charge density wave states.

Hill Heather M HM Chowdhury Sugata S Simpson Jeffrey R JR Rigosi Albert F AF Newell David B DB Berger Helmuth H Tavazza Francesca F Walker Angela R Hight ARH

Physical review. B 20190101

Metallic transition metal dichalcogenides, such as tantalum diselenide (TaSe2), display quantum correlated phenomena of superconductivity and charge density waves (CDW) at low temperatures. Here, the photophysics of 2H-TaSe2 during CDW transitions is revealed by combining temperature-dependent, low-frequency Raman spectroscopy and density functional theory (DFT). The spectra contain amplitude, phase, and zone-folded modes that are assigned to specific phonons and lattice restructuring ...[more]

PMID: 31579258

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