Nodeless superconductivity in LuRhSn with broken time reversal symmetry
arXiv:2101.10571 · doi:10.1103/PhysRevB.103.024503
Abstract
Evidence for broken time reversal symmetry (TRS) has been found in the superconducting states of the RhSn (R = Sc, Y, Lu) compounds with a centrosymmetric caged crystal structure, but the origin of this phenomenon is unresolved. Here we report neutron diffraction measurements of single crystals with =Lu, as well as measurements of the temperature dependence of the magnetic penetration depth using a self-induced tunnel diode-oscillator (TDO) based technique, together with band structure calculations using density functional theory. Neutron diffraction measurements reveal that the system crystallizes in a tetragonal caged structure, and that one of nominal Lu sites in the LuRhSn structure is occupied by Sn, yielding a composition LuRhSn (). The low temperature penetration depth shift exhibits an exponential temperature dependence below around , giving clear evidence for fully gapped superconductivity. The derived superfluid density is reasonably well accounted for by a single gap -wave model, whereas agreement cannot be found for models of TRS breaking states with two-component order parameters. Moreover, band structure calculations reveal multiple bands crossing the Fermi level, and indicate that the aforementioned TRS breaking states would be expected to have nodes on the Fermi surface, in constrast to the observations.
9 pages, 6 figures
References in corpus (10)
- High Resolution Polar Kerr Effect Measurements of Sr2RuO4: Evidence for Broken Time Reversal Symmetry in the Superconducting State
- Magnetic Penetration Depth in Unconventional Superconductors
- Evidence for time-reversal symmetry breaking in the non-centrosymmetric superconductor LaNiC
- Time-reversal symmetry breaking in noncentrosymmetric superconductor Re6Hf:further evidence for unconventional behaviour in the alpha-Mn family of materials
- Relativistic analysis of the pairing symmetry of the noncentrosymmetric superconductor LaNiC
- Simultaneous Nodal Superconductivity and Time-Reversal Symmetry Breaking in the Noncentrosymmetric Superconductor CaPtAs
- Nodeless superconductivity and time-reversal symmetry breaking in the noncentrosymmetric superconductor Re24Ti5
- Broken time-reversal symmetry probed by muon spin relaxation in the caged type superconductor LuRhSn
- Unconventional superconductivity in the cage type compound ScRhSn
- CaPtAs: a new noncentrosymmetric superconductor