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arXiv · 2311.11341

Fermi surface topology and electronic transport properties of a chiral crystal NbGe$_2$ with strong electron-phonon interaction

Yoshiki J. Sato·Ai Nakamura·Rei Nishinakayama·Ryuji Okazaki·Hisatomo Harima·Dai Aoki
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Abstract

We report the electronic structures and transport properties of a chiral crystal NbGe$_2$, which is a candidate for a coupled electron-phonon liquid. The electrical resistivity and thermoelectric power of NbGe$_2$ exhibit clear differences compared to those of NbSi2 even though both niobium ditetrelides are isostructural and isoelectronic. We discuss the intriguing transport properties of NbGe$_2$ based on a van Hove-type singularity in the density of states. The analysis of de Haas-van Alphen oscillations measured by the field modulation and magnetic torque methods reveals the detailed shape of the Fermi surface of NbGe$_2$ by comparison with the results of energy band structure calculations using a local density approximation. The electron and hole Fermi surfaces of NbGe$_2$ split into two because of the anti-symmetric spin-orbit interaction. The temperature dependence of quantum oscillations indicates that the effective mass is isotropically enhanced in NbGe$_2$ due to strong electron-phonon interaction.

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Yoshiki J. Sato, Ai Nakamura, Rei Nishinakayama, Ryuji Okazaki, Hisatomo Harima, Dai Aoki. 2023-11-19. Fermi surface topology and electronic transport properties of a chiral crystal NbGe$_2$ with strong electron-phonon interaction. https://arxiv.org/abs/2311.11341

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