Phase transitions between topologically distinct gapped phases in isotropic spin ladders

Citation
Eh. Kim et al., Phase transitions between topologically distinct gapped phases in isotropic spin ladders, PHYS REV B, 62(22), 2000, pp. 14965-14974
Citations number
36
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
PHYSICAL REVIEW B
ISSN journal
01631829 → ACNP
Volume
62
Issue
22
Year of publication
2000
Pages
14965 - 14974
Database
ISI
SICI code
0163-1829(200012)62:22<14965:PTBTDG>2.0.ZU;2-C
Abstract
We consider various two-leg ladder models exhibiting gapped phases. All of these phases have short-ranged valence bond ground states, and they all exh ibit string order. However, we show that short-ranged valence bond ground s tates divide into two topologically distinct classes, and as a consequence, there exist two topologically distinct types of string order. Therefore, n ot all gapped phases belong to the same universality class. We show that ph ase transitions occur when we interpolate between models belonging to diffe rent topological classes, and we study the nature of these transitions.