Fractional spin excitations and conductance in the spiral-staircase Heisenberg ladder

  title={Fractional spin excitations and conductance in the spiral-staircase Heisenberg ladder},
  author={Flavio Ronetti and Daniel Loss and Jelena Klinovaja},
  journal={Physical Review B},
We investigate theoretically the spiral staircase Heisenberg spin-1 / 2 ladder in the presence of antiferromagnetic long-range spin interactions and a uniform magnetic field. As a special case we also consider the Kondo necklace model. If the magnetizations of the two chains forming the ladder satisfy a certain resonance condition, involving interchain couplings as perturbations, the system is in a partially gapped magnetic phase hosting excitations characterized by fractional spins, whose… 

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