Physics – Condensed Matter – Strongly Correlated Electrons
Scientific paper
2005-05-24
Phys.Rev.B 73, 172411(2006)
Physics
Condensed Matter
Strongly Correlated Electrons
Scientific paper
10.1103/PhysRevB.73.172411
We propose that a valence-bond-solid (VBS) order can be stabilized in certain two-dimensional antiferromagnets due to spin-lattice coupling. In contrast to the VBS state of the Affleck-Kennedy-Lieb-Tesaki (AKLT) type in which the spin $2S$ and the lattice coordination $z$ must be commensurate, the spin-lattice coupling-induced VBS state can occur when $2S$ is not an integer multiple of $z$. As a concrete example, S=2 spins on the triangular network with $z=6$ is discussed. Within the Schwinger boson mean-field theory it is shown that the ground state is given by the $\sqrt{3}\times\sqrt{3}$ modulation of the valence bond amplitudes for sufficiently strong spin-lattice coupling. Using the corresponding AKLT wave function, we work out the excitation spectrum for this state within the single-mode approximation. The calculated spectrum should provide a new type of collective mode which is distinct from the spin wave excitations of the magnetically ordered ground state.
Han Jung Hoon
Jia Chenglong
No associations
LandOfFree
Valence-bond-solid order in antiferromagnets with spin-lattice coupling does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Valence-bond-solid order in antiferromagnets with spin-lattice coupling, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Valence-bond-solid order in antiferromagnets with spin-lattice coupling will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-72449