Abstract
Full text: In many transition metal oxides such as manganites the strongly interacting d electrons have both spin and orbital degrees of freedom. Decades ago Kugel and Khomskii derived the effective spin-orbital model for such systems. We investigate the phase diagram of the two-dimensional spin-orbital model in both the weak and strong limits of the quartic spin-orbital exchange interaction. This allows us to study quantum phase transitions in the model and to approach from both sides the most interesting intermediate-coupling regime and in particular the SU(4)-symmetric point of the Hamiltonian. It was suggested earlier by Li et al. that at this point the ground state of the system is a plaquette spin-orbital liquid. We argue that the state is more complex. There is plaquette order, but it is anisotropic: bonds in one direction are stronger than those in the perpendicular direction. This order is somewhat similar to that found recently in the frustrated J{sub 1}-J{sub 2} Heisenberg spin model.
Zasinas, E;
Sushkov, O P;
Oitmaa, J
[1]
- University of New South Wales, Sydney, NSW (Australia). School of Physics
Citation Formats
Zasinas, E, Sushkov, O P, and Oitmaa, J.
Phase diagram of the spin-orbital model on the square lattice.
Australia: N. p.,
2002.
Web.
Zasinas, E, Sushkov, O P, & Oitmaa, J.
Phase diagram of the spin-orbital model on the square lattice.
Australia.
Zasinas, E, Sushkov, O P, and Oitmaa, J.
2002.
"Phase diagram of the spin-orbital model on the square lattice."
Australia.
@misc{etde_20619936,
title = {Phase diagram of the spin-orbital model on the square lattice}
author = {Zasinas, E, Sushkov, O P, and Oitmaa, J}
abstractNote = {Full text: In many transition metal oxides such as manganites the strongly interacting d electrons have both spin and orbital degrees of freedom. Decades ago Kugel and Khomskii derived the effective spin-orbital model for such systems. We investigate the phase diagram of the two-dimensional spin-orbital model in both the weak and strong limits of the quartic spin-orbital exchange interaction. This allows us to study quantum phase transitions in the model and to approach from both sides the most interesting intermediate-coupling regime and in particular the SU(4)-symmetric point of the Hamiltonian. It was suggested earlier by Li et al. that at this point the ground state of the system is a plaquette spin-orbital liquid. We argue that the state is more complex. There is plaquette order, but it is anisotropic: bonds in one direction are stronger than those in the perpendicular direction. This order is somewhat similar to that found recently in the frustrated J{sub 1}-J{sub 2} Heisenberg spin model.}
place = {Australia}
year = {2002}
month = {Jul}
}
title = {Phase diagram of the spin-orbital model on the square lattice}
author = {Zasinas, E, Sushkov, O P, and Oitmaa, J}
abstractNote = {Full text: In many transition metal oxides such as manganites the strongly interacting d electrons have both spin and orbital degrees of freedom. Decades ago Kugel and Khomskii derived the effective spin-orbital model for such systems. We investigate the phase diagram of the two-dimensional spin-orbital model in both the weak and strong limits of the quartic spin-orbital exchange interaction. This allows us to study quantum phase transitions in the model and to approach from both sides the most interesting intermediate-coupling regime and in particular the SU(4)-symmetric point of the Hamiltonian. It was suggested earlier by Li et al. that at this point the ground state of the system is a plaquette spin-orbital liquid. We argue that the state is more complex. There is plaquette order, but it is anisotropic: bonds in one direction are stronger than those in the perpendicular direction. This order is somewhat similar to that found recently in the frustrated J{sub 1}-J{sub 2} Heisenberg spin model.}
place = {Australia}
year = {2002}
month = {Jul}
}