The electronic structure of 4d transition-metal monatomic wires

Abstract

Monatomic nanowires of the nonmagnetic transition metals Ru, Rh, and Pd have beenstudied theoretically, using first-principles computational techniques, in order toinvestigate the possible onset of magnetism in these nanosystems. Our fully relativisticspin-polarized all-electron density functional calculations reveal the onset of Hund’s rulemagnetism in nanowires of all three metals, with mean-field moments of 1.1, 0.3, and0.7 μB, respectively, at the equilibrium bond length. An analysis of the band structures indicatesthat the nanocontact superparamagnetic state suggested by our calculations should affectthe ballistic conductance between tips made of Ru, Rh or Pd, leading to possibletemperature and magnetic field dependent conductance.