Two-gap to Single-gap Superconducting Transition on a Honeycomb Lattice in Ca${}_{1-x}$Sr${}_x$AlSi

Abstract

It is a well-established fact that the physical properties of compounds follow their crystal symmetries. This has especially pronounced implications on emergent collective quantum states in materials. Specifically, the effect of crystal symmetries on the properties of superconductors is widely appreciated, although the clarification of this relationship is a core effort of on-going research. Emergent phenomena on honeycomb lattices are of special interest, as they can give rise to spectacular phenomenology, as manifested by the recent discovery of correlated states in magic-angle graphene, or by the high-temperature superconductivity in MgB${}_2$. Here, we report on the structural and microscopic superconducting properties of a class of ternary superconductors with Al/Si honeycomb layers, i.e. Ca${}_{1-x}$Sr${}_x$AlSi. We show that this solid solution is a remarkable model system with a highly tunable two-gap to single-gap superconducting system on a honeycomb lattice, where the superconductivity is enhanced by a subtle structural instability, i.e. the buckling of the Al/Si layers.

References in corpus (30)

• Magic-angle graphene superlattices: a new platform for unconventional superconductivity
• Boron Isotope Effect in Superconducting MgB${}_2$
• Superconductivity in the Intercalated Graphite Compounds C6Yb and C6Ca
• Pressure induced superconductivity in CaFe${}_2$As${}_2$
• musrfit: A free platform-independent framework for muSR data analysis
• Spin-polarized muons in condensed matter physics
• Magnetic Penetration Depth in Unconventional Superconductors
• Properties of the Ideal Ginzburg-Landau Vortex Lattice
• Electronic structure of superconducting graphite intercalate compounds: The role of the interlayer state
• Electronic Structure, Electron-Phonon Coupling, and Multiband Effects in MgB2
• Evidence for Time-Reversal-Symmetry-Broken Superconductivity in Locally Noncentrosymmetric SrPtAs
• Chiral $d$-wave Superconductivity in SrPtAs
• Evidence for complex order parameter in La_{1.83}Sr_{0.17}CuO_4
• Possible topologically non-trivial superconducting order parameter in type-II Weyl semimetal T_d-MoTe_2
• Intercalant-Driven Superconductivity in YbC${}_6$ and CaC${}_6$
• Superconductivity in the Honeycomb-Lattice Pnictide SrPtAs
• Evolution of two-gap behavior of the superconductor FeSe_1-x
• Muon-spin rotation studies of SmFeAsO_0.85 and NdFeAsO_0.85 superconductors
• High pressure research using muons at the Paul Scherrer Institute
• Superconductivity in the C32 Intermetallic Compounds AAl(2-x)Si(x), with A=Ca and Sr, and 0.6<x<1.2
• Muon-spin-relaxation study of the magnetic penetration depth in MgB2
• Thermodynamic Properties and Pressure Effect on the Superconductivity in CaAlSi and SrAlSi
• The emergence of superconductivity in BaNi2(Ge1-xPx)2 at a structural instability
• Direct evidence for the emergence of a pressure induced nodal superconducting gap in the iron-based superconductor Ba_0.65Rb_0.35Fe_2As_2
• Nodeless Superconductivity and its Evolution with Pressure in the Layered Dirac Semimetal 2M-WS_2
• Muon spin rotation investigation of the pressure effect on the magnetic penetration depth in YBa2Cu3Ox
• London Penetration Depth and Pair Breaking
• Conventional superconductivity and charge-density-wave ordering in Ba1-xNaxTi2Sb2O
• Pressure effects on the superconducting transition in nH-CaAlSi
• Origin of the pressure-dependent T${}_c$ valley in superconducting simple cubic phosphorus

Cited by in corpus (5)

• Chemical Principles of Intrinsic Topological Superconductors
• Ta4CoSi: a Tantalum-rich superconductor with a honeycomb network structure
• An intermediate phase induced by dilution in a correlated Dirac Fermi system
• Structural Phase Transition and Superconductivity in 2H-BaGaGe with Buckled Honeycomb Layers
• Subtle Structural Anomaly under Compression in Line-Nodal CaSb${}_2$