Petit S, Moussa F, Hennion M, Pailhès S, Pinsard-Gaudart L, Ivanov A
Laboratoire Léon Brillouin, CEA-CNRS, CE-SACLAY, F-91191 Gif sur Yvette, France.
Phys Rev Lett. 2007 Dec 31;99(26):266604. doi: 10.1103/PhysRevLett.99.266604. Epub 2007 Dec 28.
Inelastic neutron scattering measurements have been performed on YMnO3, aiming to study the interplay between spin and lattice degrees of freedom in this hexagonal multiferroic material. Our study provides evidence for a strong coupling between magnons and phonons, evidenced by the opening of a gap below T(N) in the dispersion of the transverse acoustic phonon mode polarized along the ferroelectric axis. The resulting upper phonon branch is found to lock on one of the spin-wave modes. These findings are discussed in terms of a possible hybridization between the two types of elementary excitations.
已对YMnO₃进行了非弹性中子散射测量，旨在研究这种六角形多铁性材料中自旋与晶格自由度之间的相互作用。我们的研究为磁振子与声子之间的强耦合提供了证据，这表现为沿铁电轴极化的横向声子模色散在T(N)以下出现能隙。结果发现，产生的上部声子分支锁定在其中一个自旋波模式上。将根据这两种基本激发之间可能的杂化来讨论这些发现。
