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arXiv · 2511.11105

Optical conductivity of layered topological semimetal TaNiTe$_5$

Jakov Budić·Serena Nasrallah·D. Santos-Cottin·F. Le Mardelé·A. Pulkkinen·J. Minár·P. Sačer·B. Gudac·N. Barišić·C. C. Homes·Ana Akrap·Mario Novak
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Abstract

We present an infrared spectroscopy study of the layered topological semimetal TaNiTe$_5$, a material with a quasi-one-dimensional structure and strong in-plane anisotropy. Despite its structural features, infrared reflectivity and electronic transport measurements along the $a$ and $c$ crystallographic axes show metallic behavior without evidence of reduced dimensionality. Optical conductivity reveals an anisotropic but conventional metallic response with low scattering rates and a single sharp infrared-active phonon mode at $396$ cm$^{-1}$ ($49$ meV). Ab initio calculations closely match the experimental optical data and confirm a three-dimensional electronic structure. Our results demonstrate that TaNiTe$_5$ behaves as a three-dimensional anisotropic semimetal in its electronic and optical properties.

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Jakov Budić, Serena Nasrallah, D. Santos-Cottin, F. Le Mardelé, A. Pulkkinen, J. Minár, P. Sačer, B. Gudac, N. Barišić, C. C. Homes, Ana Akrap, Mario Novak. 2025-11-14. Optical conductivity of layered topological semimetal TaNiTe$_5$. https://arxiv.org/abs/2511.11105

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