Tunable rotons in square lattice antiferromagnets under strong magnetic fields
Strongly Correlated Electrons
2014-07-23 v3
Abstract
Excitation spectra of square lattice Heisenberg antiferromagnets in magnetic fields are investigated by the spin-wave theory. It is pointed out that a rotonlike structure appears in a narrow range of magnetic fields, as a result of strong nonlinear effects. It is shown that the energy gap and the mass of the "roton" are quite sensitive to the magnetic field: the roton gap softens rapidly and eventually closes as a precursor of a quantum phase transition. The possibility of the experimental observation of the roton and a new ground state after its softening are discussed.
Keywords
Cite
@article{arxiv.1403.5870,
title = {Tunable rotons in square lattice antiferromagnets under strong magnetic fields},
author = {Yurika Kubo and Susumu Kurihara},
journal= {arXiv preprint arXiv:1403.5870},
year = {2014}
}
Comments
9 pages, 6 figures