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Title: Investigation of pressure-driven superconductivity in TlInTe 2 : an ab initio study

The Zintl compound TlInTe2is an intriguing material because of its outstanding thermoelectric properties at ambient pressure. Interestingly, it has recently been found that TlInTe2exhibits a V-shape dependence of the superconducting critical temperature (Tc) under increasing pressure, which has been linked to the reversed behavior of the Raman active Agphonon mode and anharmonic effects. In this study, we have performed first-principles calculations of the electron-phonon interactions and the superconducting properties of TlInTe2in order to understand this unusual pressure-induced response. In contrast to experiment, we find a dome-shaped pressure-induced dependence ofTcwith a maximum value of 0.23 K at 18 GPa, significantly lower than the experimental results. Electron doping has the potential to adjust theTcto fall within the experimental range, but it necessitates considerably high levels of doping. Furthermore, our analysis of the phonon spectra and phonon lifetimes, including anharmonic effects, show that anharmonicity is unlikely to influence the superconducting properties of TlInTe2. It remains an open question whether there is indeed an unusual V-shapeTcdependence with pressure or whether the phonon-mediated theory of superconductivity used here breaks down in this system.

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Author(s) / Creator(s):
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
Physica Scripta
Medium: X Size: Article No. 085962
Article No. 085962
Sponsoring Org:
National Science Foundation
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