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Pressure-induced iso-structural phase transition and metallization in WSe₂.

ABSTRACT: We present in situ high-pressure synchrotron X-ray diffraction (XRD) and Raman spectroscopy study, and electrical transport measurement of single crystal WSe₂ in diamond anvil cells with pressures up to 54.0-62.8?GPa. The XRD and Raman results show that the phase undergoes a pressure-induced iso-structural transition via layer sliding, beginning at 28.5?GPa and not being completed up to around 60?GPa. The Raman data also reveals a dominant role of the in-plane strain over the out-of plane compression in helping achieve the transition. Consistently, the electrical transport experiments down to 1.8?K reveals a pressure-induced metallization for WSe₂ through a broad pressure range of 28.2-61.7?GPa, where a mixed semiconducting and metallic feature is observed due to the coexisting low- and high-pressure structures.

SUBMITTER: Wang X

PROVIDER: S-EPMC5415762 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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Pressure-induced iso-structural phase transition and metallization in WSe2.

Wang Xuefei X Chen Xuliang X Zhou Yonghui Y Park Changyong C An Chao C Zhou Ying Y Zhang Ranran R Gu Chuanchuan C Yang Wenge W Yang Zhaorong Z

Scientific reports 20170504

We present in situ high-pressure synchrotron X-ray diffraction (XRD) and Raman spectroscopy study, and electrical transport measurement of single crystal WSe2 in diamond anvil cells with pressures up to 54.0-62.8 GPa. The XRD and Raman results show that the phase undergoes a pressure-induced iso-structural transition via layer sliding, beginning at 28.5 GPa and not being completed up to around 60 GPa. The Raman data also reveals a dominant role of the in-plane strain over the out-of p ...[more]

PMID: 28470169

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