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arXiv · 2503.17729

Anisotropic superconductivity in the quasi-one-dimensional superconductor V$_2$Ga$_5$

G. Lamura·D. Tay·R. Khasanov·P. Gentile·C. Q. Xu·X. Ke·I. J. Onuorah·P. Bonfà·Xiaofeng Xu·T. Shiroka
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Abstract

The intermetallic quasi-one-dimensional binary superconductor V$_2$Ga$_5$ was recently found to exhibit a topologically nontrivial normal state, making it a natural candidate for a topological superconductor (TSC). By combining dc-magnetization, nuclear magnetic resonance (NMR), and muon-spin rotation ({$μ$SR) measurements on high-quality V$_2$Ga$_5$ single crystals, we investigate the electronic properties of its normal- and superconducting (SC) ground states. NMR measurements in the normal state indicate a strong anisotropy in both the line shifts and the relaxation rates. Such anisotropy persists also in the superconducting state, as shown by the magnetization- and $μ$SR-spectroscopy results. In the latter case, data collected at different temperatures, pressures, and directions of the magnetic field evidence a fully-gapped, strongly anisotropic superconductivity. At the same time, hydrostatic pressure is shown to only lower the $T_c$ value, but not to change the superfluid density nor its temperature dependence. Lastly, we discuss the search for topological signatures in the normal state of V$_2$Ga$_5$, as well as a peak splitting in the FFT of the $μ$SR spectrum, possibly related to an unconventional vortex lattice. Our results suggest that V$_2$Ga$_5$ is a novel system, whose anisotropy plays a key role in determining its unusual electronic properties.

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G. Lamura, D. Tay, R. Khasanov, P. Gentile, C. Q. Xu, X. Ke, I. J. Onuorah, P. Bonfà, Xiaofeng Xu, T. Shiroka. 2025-03-22. Anisotropic superconductivity in the quasi-one-dimensional superconductor V$_2$Ga$_5$. https://doi.org/10.1038/s41598-025-94554-5

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