Experimental observation of metallic states with different dimensionality in a quasi-1D charge density wave compound

P. Rezende-Gonçalves; M. Thees; J. Rojas Castillo; D. Silvera-Vega; R. L. Bouwmeester; E. David; A. Antezak; A. J. Thakur; F. Fortuna; P. Le Fèvre; M. Rosmus; N. Olszowska; R. Magalhães-Paniago; A. C. Garcia-Castro; P. Giraldo-Gallo; E. Frantzeskakis; A. F. Santander-Syro

arXiv · 2305.00053

Experimental observation of metallic states with different dimensionality in a quasi-1D charge density wave compound

P. Rezende-Gonçalves·M. Thees·J. Rojas Castillo·D. Silvera-Vega·R. L. Bouwmeester·E. David·A. Antezak·A. J. Thakur·F. Fortuna·P. Le Fèvre·M. Rosmus·N. Olszowska·R. Magalhães-Paniago·A. C. Garcia-Castro·P. Giraldo-Gallo·E. Frantzeskakis·A. F. Santander-Syro

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Abstract

TaTe$_4$ is a quasi-1D tetrachalcogenide that exhibits a CDW instability caused by a periodic lattice distortion. Recently, pressure-induced superconductivity has been achieved in this compound, revealing a competition between these different ground states and making TaTe$_4$ very interesting for fundamental studies. Although TaTe$_4$ exhibits CDW ordering below 475 K, transport experiments have reported metallic behavior with a resistivity plateau at temperatures lower than 10 K. In this paper, we study the electronic structure of TaTe$_4$ using a combination of high-resolution angle-resolved photoemission spectroscopy and density functional calculations. Our results reveal the existence of the long-sought metallic states. These states exhibit mixed dimensionality, while some of them might have potential topological properties.

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P. Rezende-Gonçalves, M. Thees, J. Rojas Castillo, D. Silvera-Vega, R. L. Bouwmeester, E. David, A. Antezak, A. J. Thakur, F. Fortuna, P. Le Fèvre, M. Rosmus, N. Olszowska, R. Magalhães-Paniago, A. C. Garcia-Castro, P. Giraldo-Gallo, E. Frantzeskakis, A. F. Santander-Syro. 2023-04-28. Experimental observation of metallic states with different dimensionality in a quasi-1D charge density wave compound. https://arxiv.org/abs/2305.00053

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