Journal of Physics Condensed Matter
Heisenberg Hamiltonian with a Dzyaloshinski-Moriya interaction
Indrani Bose, Uma Bhaumik
Abstract
The spin- 1/2 ferromagnetic Heisenberg Hamiltonian with a Dzyaloshinski-Moriya interaction and in the presence of a strong magnetic field is studied in one dimension. Using the exact Bethe ansatz analysis, the excitation spectrum of one- and two-magnon states is derived. It is further shown that in certain parameter regimes the two-magnon bound state exists in the full range of allowed values of the centre-of-mass momentum wavevector k.