Joel Barker

Unconventional Superconductivity in La(7)Ir(3) Revealed by Muon Spin Relaxation: Introducing a New Family of Noncentrosymmetric Superconductor That Breaks Time-Reversal Symmetry.

The superconductivity of the noncentrosymmetric compound La(7)Ir(3) is investigated using muon spin rotation and relaxation. Zero-field measurements reveal the presence of spontaneous static or quasistatic magnetic fields below the superconducting transition temperature T(c)=2.25  K-a clear indication that the superconducting state breaks time-reversal symmetry. Furthermore, transverse-field rotation measurements suggest that the superconducting gap is isotropic and that the pairing symmetry of the superconducting electrons is predominantly s wave with an enhanced binding strength. The results indicate that the superconductivity in La(7)Ir(3) may be unconventional and paves the way for further studies of this family of materials.

Superconducting properties of Sn1−xInxTe (x=0.38–0.45) studied using muon-spin spectroscopy

The superconducting properties of Sn1−xInxTe (x=0.38–0.45) have been studied using magnetization and muon-spin rotation or relaxation (μSR) measurements. These measurements show that the superconducting critical temperature Tc of Sn1−xInxTe increases with increasing x, reaching a maximum at around 4.8 K for x=0.45. Zero-field μSR results indicate that time-reversal symmetry is preserved in this material. Transverse-field muon-spin rotation has been used to study the temperature dependence of the magnetic penetration depth λ(T) in the mixed state. For all the compositions studied, λ(T) can be well described using a single-gap s-wave BCS model. The magnetic penetration depth at zero temperature λ(0) ranges from 500 to 580 nm. Both the superconducting gap Δ(0) at 0 K and the gap ratio Δ(0)/kBTc indicate that Sn1−xInxTe (x=0.38–0.45) should be considered as a superconductor with intermediate to strong coupling.

Probing the superconducting ground state of the noncentrosymmetric superconductors CaTSi3 (T = Ir, Pt) using muon-spin relaxation and rotation

The superconducting properties of CaTSi3 (where T = Pt and Ir) have been investigated using muon spectroscopy. Our muon-spin-relaxation results suggest that in both these superconductors time-reversal symmetry is preserved, while muon-spin-rotation data show that the temperature dependence of the superfluid density is consistent with an isotropic s-wave gap. The magnetic penetration depths determined from our transverse-field muon-spin-rotation spectra are found to be 448(6) and 150(7) nm for CaPtSi3 and CaIrSi3, respectively.

Superconducting and normal-state properties of the noncentrosymmetric superconductor Re3Ta

We systematically investigate the normal and superconducting properties of noncentrosymmetric

Time-reversal symmetry breaking in the noncentrosymmetric superconductor Re6Hf : further evidence for unconventional behavior in the α -Mn family of materials

{\mathrm{Re}}_{6}\mathrm{Zr}

Superconducting properties and μSR study of the noncentrosymmetric superconductor Nb0.5Os0.5

using magnetization, heat capacity, and electrical resistivity measurements. Resistivity measurements indicate

Magnetic phases of skyrmion-hosting GaV

{\mathrm{Re}}_{6}\mathrm{Zr}

_4

has poor metallic behavior and is dominated by disorder.

S

{\mathrm{Re}}_{6}\mathrm{Zr}

_{8-y}

undergoes a superconducting transition at