Pressure-induced Superconductivity in Noncentrosymmetric Weyl Semimetals LaAlX (X = Si and Ge)
arXiv:2111.02882
Abstract
In topological materials, Dirac fermions can split into two Weyl fermions with opposite chiralities due to the breaking of space inversion symmetry, while in non-centrosymmetric superconductors, novel superconducting electron pairing mechanisms arise because of the antisymmetric spin-orbit coupling. In this work, we report the pressure-introduced superconductivity in a typical noncentrosymmetric Weyl semimetal LaAlX (X=Si and Ge). Superconductivity was observed at around 65 GPa without structural phase transition. A typical dome-shape phase diagram is obtained with the maximum Tc of 2.5 K (2.1 K) for LaAlSi (LaAlGe). Furthermore, the application of pressure does not destroy the nontrivial band topology of LaAlSi up to 80.4 GPa, making such materials as potential candidates for realizing topological superconductivity. Our discovery of superconductivity in LaAlX (X=Si and Ge) will provide critical insight in noncentrosymmetric superconductors and stimulate further study on superconductivity in Weyl semimetals.
15 pages, 5 figures, 1 table
References in corpus (9)
- Computing topological invariants without inversion symmetry
- Topological Magnetic Phase in the Candidate Weyl Semimetal CeAlGe
- Time-reversal invariant topological superconductivity in doped Weyl semimetals
- Charge density wave orders and enhanced superconductivity under pressure in the kagome metal CsV3Sb5
- A new noncollinear ferromagnetic Weyl semimetal with anisotropic anomalous Hall effect
- Origin and Large Enhancement of Large Spin Hall Angle in Weyl Semimetals LaAl (=Si, Ge)
- Suppression of axionic charge density wave and onset of superconductivity in the chiral Weyl semimetal TaSeI
- Incommensurate magnetism mediated by Weyl fermions in NdAlSi
- Pressure-induced Superconductivity in dual-topological semimetal Pt2HgSe3