The pairing symmetry in quasi-one-dimensional superconductor Rb2Mo3As3

Abstract

Quasi-one-dimensional electron systems display intrinsic instability towards long-range ordered phases at sufficiently low temperatures. The superconducting orders are of particular interest as they can possess either singlet or triplet pairing symmetry and frequently compete with magnetism. Here we report on muon spin rotation and relaxation ($\mu$SR) study of Rb${}_2$Mo${}_3$As${}_3$ characterised by one of the highest critical temperatures $T_{\mathrm{c}}=10.4\mathrm{K}$ among quasi-one-dimensional superconductors. The transverse-field $\mu$SR signal shows enhanced damping below $T_{\mathrm{c}}$ due to the formation of vortex lattice. Comparison of vortex lattice broadening against single gap $s-$, $p-$ and $d-$wave models shows the best agreement for the $s-$wave scenario but with the anomalously small superconducting gap, ${\Delta }_0$, to $T_{\mathrm{c}}$ ratio of $2{\Delta }_0/k_{\mathrm{B}}{T}_{\mathrm{c}}=2.74(1)$. The alternative nodal $p-$wave or $d-$wave scenarios with marginally worse goodness of fit would yield more realistic $2{\Delta }_0/k_{\mathrm{B}}{T}_{\mathrm{c}}=3.50(2)$ and $2{\Delta }_0/k_{\mathrm{B}}{T}_{\mathrm{c}}=4.08(1)$, respectively, and thus they cannot be ruled out when accounting for the superconducting state in Rb${}_2$Mo${}_3$As${}_3$.

arXiv comment6 pages

References in corpus (22)

• Nearly Isotropic superconductivity in (Ba,K)Fe2As2
• musrfit: A free platform-independent framework for muSR data analysis
• Magnetic Penetration Depth in Unconventional Superconductors
• Properties of the Ideal Ginzburg-Landau Vortex Lattice
• Superconductivity in quasi-one-dimensional K${}_2$Cr${}_3$As${}_3$ with significant electron correlations
• Unconventional superconductivity in quasi-one-dimensional Rb${}_2$Cr${}_3$As${}_3$
• The new versatile general purpose surface-muon instrument (GPS) based on silicon photomultipliers for $\mu$SR measurements on a continuous-wave beam
• NMR Investigation of the Quasi One-dimensional Superconductor K${}_2$Cr${}_3$As${}_3$
• Searching for triplet superconductivity in the Quasi-One-Dimensional K2Cr3As3
• Triplet $p_z$-wave pairing in quasi one dimensional A${}_2$Cr${}_3$As${}_3$ superconductors
• Spin-Triplet Superconductivity in K2Cr3As3
• Multiband one-dimensional electronic structure and spectroscopic signature of Tomonoga-Luttinger liquid behavior in K${}_2$Cr${}_3$As${}_3$
• Superconductivity at 10.4 K in a novel quasi-one-dimensional ternary molybdenum pnictide K2Mo3As3
• Nodal superconducting gap structure in the quasi-one-dimensional Cs${}_2$Cr${}_3$As${}_3$ investigated using $\mu$SR measurements
• Coexistence of nontrivial topological properties and strong ferromagnetic fluctuations in $A_2$Cr${}_3$As${}_3$ ($A$=Na, K, Rb and Cs)
• Coupling of structure to magnetic and superconducting orders in quasi-one-dimensional ${\text{K}}_2{\text{Cr}}_3{\text{As}}_3$
• Evidence of nodal gap structure in the basal plane of the FeSe superconductor
• ${}^{133}$Cs and ${}^{75}$As NMR investigation of the normal metallic state of the quasi-one-dimensional Cs${}_2$Cr${}_3$As${}_3$
• Multigap superconductivity in RbCa2Fe4As4F2 investigated using muSR measurements
• K2Mo3As3 is a Multi-Gap Electron-Phonon Superconductor
• Gapless spin-excitations in the superconducting state of a quasi-one-dimensional spin-triplet superconductor
• Superconductivity in the regime of attractive interactions in the Tomonaga-Luttinger liquid