In this paper we explore the phase diagram and excitations of a distorted triangular lattice antiferromagnet. The unique two-dimensional distortion considered here is very different from the 'isosceles'-type distortion that has been extensively investigated. We show that it is able to stabilize a 120{\deg} spin structure for a large range of exchange interaction values, while new structures are found for extreme distortions. A physical realization of this model is \alpha-CaCr2O4 which has 120{\deg} structure but lies very close to the phase boundary. This is verified by inelastic neutron scattering which reveals unusual roton-like minima at reciprocal space points different from those corresponding to the magnetic order.
@article{arxiv.1206.1795,
title = {Magnetic soft modes in the locally distorted triangular antiferromagnet alpha-CaCr2O4},
author = {S. Toth and B. Lake and K Hradil and T. Guidi and K. C. Rule and M. B. Stone and A. T. M. N. Islam},
journal= {arXiv preprint arXiv:1206.1795},
year = {2016}
}