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arXiv · 1807.08472

Three-dimensional Fermi surface of 2H-NbSe$_2$ - Implications for the mechanism of charge density waves

F. Weber·R. Hott·R. Heid·L. L. Lev·M. Caputo·T. Schmitt·V. N. Strocov
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Abstract

We investigate the three-dimensional electronic structure of the seminal charge-density-wave (CDW) material 2H-NbSe$_2$ by soft x-ray angle-resolved photoelectron spectroscopy and density-functional theory. Our results reveal the pronounced 3D character of the electronic structure formed in the quasi-two-dimensional layered crystal structure. In particular, we find a strong dispersion along $k_z$ excluding a nesting-driven CDW formation based on experimental data. The 3D-like band structure of 2H-NbSe$_2$ has strong implications for the intriguing phase competition of CDW order with superconductivity.

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F. Weber, R. Hott, R. Heid, L. L. Lev, M. Caputo, T. Schmitt, V. N. Strocov. 2018-07-23. Three-dimensional Fermi surface of 2H-NbSe$_2$ - Implications for the mechanism of charge density waves. https://doi.org/10.1103/physrevb.97.235122

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