Pressure-induced superconductivity in charge-density-wave compound LaTe2-xSbx (x=0 and 0.4)

TL;DR

This study demonstrates that applying pressure induces superconductivity in LaTe2-xSbx compounds, with Sb doping enhancing the critical temperature, supported by experimental measurements and theoretical calculations within the BCS framework.

Contribution

It provides new insights into pressure-induced superconductivity in LaTe2-xSbx and shows how Sb doping influences the superconducting transition temperature.

Findings

Superconductivity appears at 4.6 and 2.5 GPa for x=0 and 0.4.

Sb doping increases the maximum Tc from 4.6 K to 6.5 K.

Theoretical calculations match experimental Tc and show CDW suppression under pressure.

Abstract

Here, we have grown single crystals of LaTe2-xSbx (x=0 and 0.4) with continuously adjustable CDW. High-pressure x-ray diffraction show LaTe2 does not undergo phase transition and keep robust below 40 GPa. In-situ high-pressure electrical measurements show LaTe2-xSbx undergo semiconductor-metal-superconductivity transition at 4.6 and 2.5 GPa, respectively. With the doping of Sb, the highest Tc increases from 4.6 to 6.5 K. Theoretical calculations reveal that the CDW has been completely suppressed and the calculated Tc is about 2.97 K at 4.5 GPa, consistent with the measured value. Then, the pressure-induced superconductivity in LaTe2-xSbx can be explained in the framework of the BCS theory.