Erratum: Evidence for Time-Reversal Symmetry Breaking in the Noncentrosymmetric SuperconductorLaNiC2[Phys. Rev. Lett.102, 117007 (2009).]

Abstract

We have discovered that the Ni and C atomic positions were mistyped in the data files used to generate the image of the unit cell in Fig. 3 of our Letter [1]. The same data files were used to calculate the nuclear dipole field whose contours are shown in the same figure. We provide here a corrected version of Fig. 3, obtained using the correct Ni and C positions corresponding to the fit to neutron diffraction data shown in Fig. 1 of our Letter. The crystal symmetry does not change and the effect on the dipole fields is negligible. Thus, all our other results and conclusions are unaffected.[1] A. D. Hillier, J. Quintanilla, and R. Cywinski, Phys. Rev. Lett. 102, 117007 (2009) . FIG. 3 (color online). The crystal structure of LaNiC 2 . The large red spheres are La, medium-sized blue spheres are Ni, smaller black spheres are C, and the smallest yellow sphere represents the muon. The contour plot of the nuclear dipole fields for LaNiC 2 is shown throughout the unit cell at x ¼ 1 2 and shows the muon site is at ( 1 2 , 1 2 , 0).

Muon spin rotation study of magnetism and superconductivity in Ba(Fe1−xCox)2Bernhard1, Wang2, Nuccio3 et al. 2012Phys. Rev. B5422871View full textAdd to dashboardCite

“…A similar behavior was previously observed in materials with a spin-triplet superconducting order parameter that breaks time reversal symmetry, as in Sr 2 RuO 4 , 42 PrOs 4 Sb 12 , 68 or LaNiC 2 . 69 However, such a spin-triplet state does not seem to be realized in Ba(Fe 1−x Co x ) 2 As 2 for which NMR Knight shift measurements revealed a pronounced superconductivityinduced reduction of the Knight shift that is a hallmark of a spin-singlet superconducting state. 70,71 Therefore, it appears that alternative explanations for the enhanced spin correlations in the superconducting state of optimally doped and overdoped Ba(Fe 1−x Co x ) 2 As 2 need to be explored.…”

Probing the superconducting ground state of the noncentrosymmetric superconductorsCaTSi3(T= Ir, Pt) using muon-spin relaxation and rotation

“…The possibility of mixed spinsinglet spin-triplet pairing in noncentrosymmetric superconductors makes them prime candidates to exhibit TRS breaking 6 . To date, the only truly NCS reported to show TRS breaking are LaNiC 2 and Re 6 Zr, 16,21 however, for LaNiC 2 , a mixing of singlet and triplet states is forbidden due to the symmetry of the structure 22 27 and several have been shown to exhibit unconventional superconducting behavior including features such as upper critical fields close to the Pauli limit, evidence for multiple gaps, or a significant admixture of a triplet component to the superconducting order parameter. Muon spectroscopy studies have been performed on some of these compounds e.g.…”

Tuning of superconductivity by Ni substitution into noncentrosymmetric ThCo1−xNixC2

“…[27][28][29] However, more recent experiments have observed unconventional behavior, such as intriguing time reversal symmetry (TRS) breaking in muon-spin relaxation measurements, a nodal energy gap from very-low temperature magnetic penetration depth measurements, and a proposed multi-gap superconductivity due to the moderate value of the ASOC in LaNiC2. [33][34][35] The isostructural compound ThCoC2 was recently discovered to be a new NCS superconductor with a critical temperature of Tc=2.65K. 36 The superconductivity of ThCoC2 was found to exhibit unconventional behavior with a strong positive curvature in the upper critical field Hc2 …”