Abstract
We investigate the pressure effects on the electronic structures and phonon properties of rare-earth-based cubic-Heusler compound , on the basis of density functional theory. We find the occurrence of intriguing phase transition from the superconducting (SC) to charge-density wave (CDW) state under pressure (), which is quite unusual in that the pressure is detrimental to the CDW state in usual systems. The SC transition temperature of increases first with increasing pressure, up to , above which a quantum phase transition into the CDW state takes place. This extraordinary transition originates from the occurrence of phonon softening instability at a special in the Brillouin zone. We thus propose that is a quite unique material, in which the CDW quantum critical point is realized under the SC dome by applying the pressure.
- Received 29 July 2019
- Revised 10 March 2020
- Accepted 10 September 2020
DOI:https://doi.org/10.1103/PhysRevLett.125.157001
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