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Charge Density Waves in Electron-Doped Molybdenum Disulfide.

ABSTRACT: We present the discovery of a charge density wave (CDW) ground state in heavily electron-doped molybdenum disulfide (MoS₂). This is the first observation of a CDW in any d² (column 6) transition metal dichalcogenide (TMD). The band structure of MoS₂ is distinct from the d⁰ and d¹ TMDs in which CDWs have been previously observed, facilitating new insight into CDW formation. We demonstrate a metal-insulator transition at 85 K, a 25 meV gap at the Fermi level, and two distinct CDW modulations, (2√3 × 2√3) R30° and 2 × 2, attributable to Fermi surface nesting (FSN) and electron-phonon coupling (EPC), respectively. This simultaneous exhibition of FSN and EPC CDW modulations is unique among observations of CDW ground states, and we discuss this in the context of band folding. Our observations provide a route toward the resolution of controversies surrounding the origin of CDW modulations in TMDs.

SUBMITTER: Bin Subhan MK

PROVIDER: S-EPMC8397392 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Charge Density Waves in Electron-Doped Molybdenum Disulfide.

Bin Subhan Mohammed K MK Suleman Asif A Moore Gareth G Phu Peter P Hoesch Moritz M Kurebayashi Hidekazu H Howard Christopher A CA Schofield Steven R SR

Nano letters 20210706 13

We present the discovery of a charge density wave (CDW) ground state in heavily electron-doped molybdenum disulfide (MoS2). This is the first observation of a CDW in any d2 (column 6) transition metal dichalcogenide (TMD). The band structure of MoS2 is distinct from the d0 and d1 TMDs in which CDWs have been previously observed, facilitating new insight into CDW formation. We demonstrate a metal-insulator transition at 8 ...[more]

PMID: 34228455

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