Spontaneous Plaquette Formation in the SU(4) Spin-Orbital Ladder

Mathias van den Bossche; Patrick Azaria; Philippe Lecheminant; Frédéric Mila

doi:10.1103/PhysRevLett.86.4124

Spontaneous Plaquette Formation in the SU(4) Spin-Orbital Ladder

Mathias van den Bossche, Patrick Azaria, Philippe Lecheminant, and Frédéric Mila

Phys. Rev. Lett. 86, 4124 – Published 30 April 2001

Abstract

The low-energy properties of the SU(4) spin-orbital model on a two-leg ladder are studied by a variety of analytical and numerical techniques. As in the case of SU(2) models, there is a singlet-multiplet gap in the spectrum, but the ground state is twofold degenerate. An interpretation in terms of SU(4)-singlet plaquettes is proposed. The implications for general two-dimensional lattices are outlined.

Received 30 June 2000

DOI:https://doi.org/10.1103/PhysRevLett.86.4124

Authors & Affiliations

Mathias van den Bossche¹, Patrick Azaria², Philippe Lecheminant³, and Frédéric Mila^1,4

¹Laboratoire de Physique Quantique, Université Paul Sabatier, 31062 Toulouse Cedex 04, France
²Laboratoire de Physique Théorique des Liquides, Université Pierre et Marie Curie, 75252 Paris Cedex 05, France
³Laboratoire de Physique Théorique et Modélisation, Université de Cergy-Pontoise, 95301 Cergy-Pontoise Cedex, France
⁴Institut de Physique Théorique, Université de Lausanne, CH-1015 Lausanne, Switzerland