Antiferromagnetic spin fluctuations and unconventional superconductivity in topological superconductor candidate YPtBi revealed by ${}^{195}$Pt-NMR

Abstract

We report ${}^{195}$Pt nuclear magnetic resonance (NMR) measurements on topological superconductor candidate YPtBi which has the broken inversion symmetry and topological non-trivial band structures due to the strong spin-orbit coupling(SOC). In the normal state, we find that Knight shift $K$ is field- and temperature-independent, suggesting that the contribution from the topological bands is very small at low temperatures. However, the spin-lattice relaxation rate 1/$T_1$ divided by temperature ($T$), 1/$T_{1}T$, increases with decreasing $T$, implying the existence of antiferromagnetic spin fluctuations. In the superconducting state, no Hebel-Slichter coherence peak is seen below $T_{\mathrm{c}}$ and 1/$T_1$ follows $T^3$ variation, indicating the unconventional superconductivity. The finite spin susceptibility at zero-temperature limit and the anomalous increase of the NMR line width below $T_{\mathrm{c}}$ point to a mixed state of spin-singlet and spin-triplet(or spin-septet) pairing.

arXiv comment13 pages, 5 figures, accepted for publication in Physical Review Letters

References in corpus (41)

• Topological Insulators
• Topological insulators and superconductors
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Topological Insulators with Inversion Symmetry
• Topological superconductors: a review
• Tunable Multifunctional Topological Insulators in Ternary Heusler Compounds
• A new platform for topological quantum phenomena : Topological Insulator states in thermoelectric Heusler-related ternary compounds
• Topologically-Protected Qubits from a Possible Non-Abelian Fractional Quantum Hall State
• Microscopic evidence for a chiral superconducting order parameter in the heavy fermion superconductor UTe2
• Half-Heusler Compounds as a New Class of Three-Dimensional Topological Insulators
• Spin-Rotation Symmetry Breaking in the Superconducting State of CuxBi2Se3
• Spin Triplet Superconducting State due to Broken Inversion Symmetry in Li_2Pt_3B
• Superconductivity in the topological semimetal YPtBi
• Topological $R$PdBi half-Heusler semimetals: a new family of non-centrosymmetric magnetic superconductors
• Superconductivity in the noncentrosymmetric half-Heusler compound LuPtBi : A possible topological superconductor
• Unconventional Superconductivity and Electron Correlations in Cobalt Oxyhydrate Na${}_{0.35}$CoO${}_2$$\cdot y$H${}_2$O
• Beyond Triplet: Unconventional Superconductivity in a Spin-3/2 Topological Semimetal
• Pairing of j=3/2 fermions in half-Heusler superconductors
• Observation of Unusual Topological Surface States in Half-Heusler Compounds LnPtBi (Ln=Lu, Y)
• Superconductivity in three-dimensional spin-orbit coupled semimetals
• Metallic surface electronic state in half-Heusler compounds RPtBi (R = Lu, Dy, Gd)
• Topological superconductivity of spin-3/2 carriers in a three-dimensional doped Luttinger semimetal
• Pairing states of spin-3/2 fermions: Symmetry-enforced topological gap functions
• Inflated nodes and surface states in superconducting half-Heusler compounds
• Superconductivity in non-centrosymmetric YPtBi under pressure
• Unconventional superconductivity in YPtBi and related topological semimetals
• Superconductivity of the Ternary Boride Li_2Pd_3B Probed by ^{11}B NMR
• Spin-Triplet Superconductivity in K2Cr3As3
• Unconventional Superconductivity in Luttinger Semimetals: Theory of Complex Tensor Order and the Emergence of the Uniaxial Nematic State
• Abrupt enhancement of non-centrosymmetry and appearance of the spin-triplet superconducting state in Li_2(Pd_{1-x}Pt_{x})_3B beyond x=0.8
• NMR and NQR Studies on Non-centrosymmetric Superconductors Re7B3, LaBiPt, and BiPd
• Topological septet pairing with spin-$\frac{3}{2}$ fermions -- high partial-wave channel counterpart of the ${}^3$He-B phase
• Majorana surface modes of nodal topological pairings in spin-$\frac{3}{2}$ semi-metals
• Singlet-Quintet Mixing in Spin-Orbit Coupled Superconductors with j=3/2 Fermions
• Tuning the Parity Mixing of Singlet-Septet Pairing in a Half-Heusler Superconductor
• Exotic Landau Diamagnetism and Weyl-Fermions Excitations in TaAs Revealed by ${}^{75}$As NMR and NQR
• Topological d+s wave superconductors in a multi-orbital quadratic band touching system
• Nonlinear magnetization of graphene
• $1/T_1$ in the D-wave superconducting state with coexisting antiferromagnetism
• Unconventional superconductivity and Surface pairing symmetry in Half-Heusler Compounds
• Hydration-induced anisotropic spin fluctuations in Na_{x}CoO_{2}\cdot1.3H_{2}O superconductor

Cited by in corpus (3)

• Tuning the topological character of half-Heusler systems: A comparative study on Y$T$Bi ($T$ = Pd, Pt)
• Uniform electronic states and $s$-wave superconductivity in a strongly disordered high-entropy compound (RuRhPdIr)${}_{0.6}$Pt${}_{0.4}$Sb
• Majorana modes in trapped-ion system and their Floquet engineering