Using new as well as known results on dimerized quantum spin chains with frustration, we are able to infer some properties on the low-energy spectrum of the O(3) Nonlinear Sigma Model with a topological θ-term. In particular, for sufficiently strong coupling, we find a range of values of θ where a singlet bound state is stable under the triplet continuum. On the basis of these results, we propose a new renormalization group flow diagram for the Nonlinear Sigma Model with a θ-term.
Particle content of the nonlinear sigma model with a θ-term: a lattice model investigation / L. Campos Venuti; C. Degli Esposti Boschi; E. Ercolessi; F. Ortolani; G. Morandi; S. Pasini; M. Roncaglia. - In: JOURNAL OF STATISTICAL MECHANICS: THEORY AND EXPERIMENT. - ISSN 1742-5468. - ELETTRONICO. - L02004:(2005), pp. 1-9. [10.1088/1742-5468/2005/02/L02004]
Particle content of the nonlinear sigma model with a θ-term: a lattice model investigation
DEGLI ESPOSTI BOSCHI, CRISTIAN;ERCOLESSI, ELISA;ORTOLANI, FABIO;MORANDI, GIUSEPPE;PASINI, STEFANO;RONCAGLIA, MARCO
2005
Abstract
Using new as well as known results on dimerized quantum spin chains with frustration, we are able to infer some properties on the low-energy spectrum of the O(3) Nonlinear Sigma Model with a topological θ-term. In particular, for sufficiently strong coupling, we find a range of values of θ where a singlet bound state is stable under the triplet continuum. On the basis of these results, we propose a new renormalization group flow diagram for the Nonlinear Sigma Model with a θ-term.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.