@article{jones_superconducting_2024,

title = {Superconducting transition temperatures of pure vanadium and vanadium-titanium alloys in the presence of dynamical electronic correlations},

author = {D. Jones and A. Östlin and A. Weh and F. Beiuşeanu and U. Eckern and L. Vitos and L. Chioncel},

doi = {10.1103/PhysRevB.109.165107},

year  = {2024},

date = {2024-04-01},

urldate = {2024-04-12},

journal = {Phys. Rev. B},

volume = {109},

number = {16},

pages = {165107},

abstract = {Ordinary superconductors are widely assumed insensitive to small concentrations of random nonmagnetic impurities, whereas strong disorder suppresses superconductivity, ultimately leading to a superconductor-insulator transition. In between these limiting cases, a most fascinating regime may emerge where disorder enhances superconductivity. This effect is discussed here for the β phase of vanadium-titanium alloys. Disorder is modeled using the coherent potential approximation while local electronic interactions are treated using dynamical mean-field theory. The McMillan formula is employed to estimate the superconducting transition temperature, showing a maximum at a Ti concentration of around 0.33 for a local Coulomb interaction U in the range of 2 eV to 3 eV. Our calculations quantitatively agree with the experimentally observed concentration-dependent increase of Tc, and its maximal value of about 20%.},

keywords = {},

pubstate = {published},

tppubtype = {article}

}

@article{prodan_large_2023,

title = {Large ordered moment with strong easy-plane anisotropy and vortex-domain pattern in the kagome ferromagnet Fe_{3}Sn},

author = {L. Prodan and D. M. Evans and S. M. Griffin and A. Oestlin and M. Altthaler and E. Lysne and I. G. Filippova and S. Shova and L. Chioncel and V. Tsurkan and I. Kézsmárki},

doi = {10.1063/5.0155295},

issn = {0003-6951},

year  = {2023},

date = {2023-07-01},

urldate = {2023-07-01},

journal = {Appl. Phys. Lett.},

volume = {123},

number = {2},

pages = {021901},

abstract = {We report the magnetic anisotropy of kagome bilayer ferromagnet Fe3Sn probed by the bulk magnetometry and magnetic force microscopy (MFM) on high-quality single crystals. The dependence of magnetization on the orientation of the external magnetic field reveals strong easyplane magnetocrystalline anisotropy and anisotropy of the saturation magnetization. The leading magnetocrystalline anisotropy constant shows a monotonous increase from K-1 approximate to -1.0 x 10(6) J/m(3) at 300K to -1.3 x 10(6) J/m(3) at 2K. Our ab initio electronic structure calculations yield the value of total magnetic moment of 7.1 mu(B)=f.u. and a magnetocrystalline anisotropy energy density of -0.57meV=f.u. (-1.62 x 10(6)J/m(3)) both being in reasonable agreement with the experimental values. The MFM imaging reveals micrometer-scale magnetic vortices with weakly pinned cores that vanish at the saturation field of similar to 3T applied perpendicular to the kagome plane. The observed vortex-domain structure is well reproduced by the micromagnetic simulations, using the experimentally determined value of the anisotropy and exchange stiffness. (c) 2023 Author(s).},

keywords = {},

pubstate = {published},

tppubtype = {article}

}